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Alpine KTP-445U Power Pack

Compact upgrade for any car radio — 45 watts RMS X 4

189 Reviews | 59 questions - 125 answers

Item # 500KTP445U

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Our take on the Alpine KTP-445U Power Pack

Want a simple way to crank up the power of your receiver? Alpine's "Power Pack" amplifier increases your receiver's power output to 45 watts RMS by 4 channels. That's a big jump up from the 7-20 watts per channel typically put out by a car radio, and plenty of power to drive high-performance speakers or keep up with a big subwoofer amplifier. Best of all, this compact amplifier is so efficient you can often run it off the same circuit that powers your receiver. A universal plug lets you feed a signal via RCA outputs or speaker-level wiring.

Alpine Authorized Online Dealer

More power, less hassle

Want a simple way to crank up the power of your receiver? Alpine's "Power Pack" amplifier increases your receiver's power output to 45 watts RMS by 4 channels. That's a big jump up from the 7-20 watts per channel typically put out by a car radio, and plenty of power to drive high-performance speakers or keep up with a big subwoofer amplifier. Best of all, this compact amplifier is so efficient you can often run it off the same circuit that powers your receiver. A universal plug lets you feed a signal via RCA outputs or speaker-level wiring.

You can install this compact amp behind most dashboards, but you'll need 4-channel patch cables to connect your car stereo to the amp's preamp inputs. You can also splice into your speaker wiring to get signal to the KTP-445U.

Installation Note: We recommend running a dedicated constant power wire to the battery for optimal performance from this Alpine amp — we offer an inexpensive wiring kit for this installation. This high-powered amp won't work in systems where an outboard factory amplifier is still active.

Product Highlights:

  • compact Class D amplifier for factory and aftermarket receivers
  • universal plug lets you send signal from RCA outputs or speaker-level wiring
  • 4-channel amplifier
  • 45 watts RMS x 4 at 4 ohms (CEA-2006 compliant)
  • built-in high-pass crossover (selectable 60, 80, 120 Hz at 12 dB/octave)
  • selectable gain switch (high/low) and switchable 2- or 4-channel operation
  • fuse: 15A
  • dimensions: 7-7/8"W x 1-1/2"H x 2-9/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

  • Head Unit Power Pack
  • 15-amp ATM mini-blade fuse (installed)
  • 30" Power/speaker-output harness
  • 5.5" Speaker-level/low-level input harness (Turn-on lead is 40" long)
  • 2 Metal brackets
  • 4 Phillips/Hex-head mounting screws
  • 4 Wire-ties
  • Owner's Manual (English/ French/ Spanish)
  • Limited Warranty card
  • "Thank You" letter

I installed this to increase the volume of the stock head unit in my 2010 Toyota Tacoma, which didn't get very loud, especially the AUX input. It did the trick, and the stock speakers seem to handle the output fine.

Anonymous, Santa Cruz, CA


Alpine KTP-445U Power Pack Reviews

Average Customer Review(s):

(189 Reviews)

Alpine KTP-445U Power Pack

Anonymous from Santa Cruz, CA on 1/21/2018

Crutchfield Customer Review (What's this?)

I installed this to increase the volume of the stock head unit in my 2010 Toyota Tacoma, which didn't get very loud, especially the AUX input. It did the trick, and the stock speakers seem to handle the output fine.

Pros: Boosts the power of the stock head unit nicely.

Cons: A bit tricky to install in the vehicle, more an issue of the car than the unit, which is pretty small.

Alpine KTP-445U

Anonymous from Lupton, MI on 11/14/2017

Crutchfield Customer Review (What's this?)

Blow my hair back?? I didn't think there was going to be that big of a difference in loudness or clarity. Everything is much better with Crutchfield and their staff. Thanks to staff like Paul.



Alpine KTP-445U Power Pack

Anonymous from Cool Ridge, WV on 10/27/2017

Crutchfield Customer Review (What's this?)

Was very surprised at the amount of power supplied by this small amp, more than enough to double the sound and quality of any factory system, highly recommend.



Adds plenty of volume and upgrades detail!!

Dexter from Norton VA on 10/18/2017

Crutchfield Customer Review (What's this?)

I love this amplifier! I'm a big Jeep guy, and nothing upgrades the sound in your JK quite like this little amplifier. For the newer (non Alpine or Infinity models) Jeep Wrangler's, this amplifier is completely plug-and-play. Just pair it with an Alpine stereo and you're good to go! Drop the top or take out the roof panels, turn up the radio, and enjoy excellent quality music LOUD!

Pros: completely plug-and-play in many cars.

Cons: It could be more powerful, but that's an issue I'm always faced with.

Alpine KTP-445U Power Pack

RICHARD from Tacoma, WA on 10/11/2017

Crutchfield Customer Review (What's this?)

Awesome product!!! I expected nothing less from Alpine. Powers my Kicker component's for both the front and rear doors with zero distortion. sounded great with the stock speakers as well. easy wiring completely plug and play and can fit anywhere.

Pros: great power great sound compact size great price easy install

Cons: havent found one yet...

Nice amp

Steve from Morrilton, AR on 9/5/2017

Crutchfield Customer Review (What's this?)

Perfect amp for the Miata

Pros: Perfect fit for a in dash install. Really makes my JVC head unit sound great.

Cons: None as of yet

Review correction/update for 2015 Subaru Forester install

BFC from Seattle, WA on 8/28/2017

Last February 2016 I gave the amp a poor review because of a hum noise I was getting thru my speakers , using the oem Clarion head unit and upgraded Subaru Kicker speakers. Used speaker level connection. I've since replaced the stock head unit with a Kenwood Excelon DPX792BH bought thru Crutchfield and decided to try using the Alpine again, this time using RCA connections and the amp was powered and grounded again using the car's radio power and ground wires. No hum or any other issues so it seems the switch to a better head unit w/ rca inputs did the trick. I also followed Crutchfield's advice on using test tones to help set the gains. I wasn't expecting a huge jump in power (Kenwood head unit 22 watts/channel, Alpine 45watts/channel) but there is a bit more oomph and clarity to the sound now so any issues I had before weren't due to this Alpine amp.

Pros: Small size, relatively cool-running, uses RCA connection, good value


Great amp

nathan from Kansas City, MO on 8/20/2017

Crutchfield Customer Review (What's this?)

Great little amp with lots of power.

Pros: Bought this amp to power the door speakers in my 2016 Dodge Ram 2500. Used in a previous vehicle. Sounded great and was easy to hide. Most people thought I was using a much bigger amp to power my speakers. Loved it and will suggest to anyone looking for an easy clean install amp to purchase.

Cons: When turned up it would cut out. It may have been due to heat. This was an early generation amp, I would expect Alpine to have corrected the issue over the years


James from San Antonio, TX on 8/3/2017

Crutchfield Customer Review (What's this?)

This little guy has way more power than advertised. Had good features, can install pretty much anywhere. Great solution if tight on space or just trying to beef up any deck.

Pros: Power, size, ease of use

Cons: None


Sparky from Newport News Va. on 7/20/2017

Crutchfield Customer Review (What's this?)

Install this on my 2009 Street Glide to power to Alpine 6.5 Bridge and it's a perfect product fits in the fairing perfect.

Pros: Compact size and power when bridged

Cons: Really none for the application that I had for my motorcycle

Amazing power from a small package

James from Wappingers Falls, NY on 6/21/2017

Crutchfield Customer Review (What's this?)

Great power and sound from a small package. Install was a bit annoying due to the numerous and bulky wires.

Pros: Amazing power from a small package. Easy to find a space to install. Surprisingly loud given modest specs. Would buy again.

Cons: Having wiring harness on each end makes installation more difficult. Prefer to see all wires on one side for better "fitability". Simply the wiring as well.

I cant feel the difference

Don2 from Aliso Viejo on 5/8/2017

I bought mine at a local dealer. This store is in Rancho Sta Margarita in California. I purchased this to give my Pioneer Avic 5200 NEX an extra power. Honestly i cant feel the difference. I have a friend who has the same head unit and has a cheaper speaker component speaker and his sounds louder and cleaner than mine. I will have mine removed next week. It was not worth it. If you expect more power, this wont serve the purpose. Do not get this one. I am an audiophile for decades and I will go back to either Rockford Fosgate or JL audio. Alpine is not very popular with amps. Again do not buy this. I gave mine a chance but didn't satisfy me

Pros: Cheap, can be installed bahind the dash

Cons: Cant feel its presence, its just like as powerful as a head unit

Alpine KTP-445U Power Pack

Anonymous from Blue Ridge, va on 5/8/2017

Crutchfield Customer Review (What's this?)

Have not connected it yet but the size was very compact. Exactly what we wanted.

Pros: Compact size


Great sound improvement

Robert from Olympia, WA on 4/22/2017

Crutchfield Customer Review (What's this?)

Love the sound this little amp kicks out. It gives the speaker in my Tundra the extra boost of power to really improve the sound quality. It's size allows you to mount it just about anywhere.

Pros: Great sound, compact size

Cons: None!!!

Alpine KTP-445U Power Pack

Anonymous from Barrigada, Guam on 4/18/2017

Crutchfield Customer Review (What's this?)

Powerful Amp for its size. I ended up mounting it on the driver's side kick panel for easier access for tuning the amp.



Makes Honda CRV a pleasure to drive

dominic from Wakefield, MA on 4/16/2017

Crutchfield Customer Review (What's this?)

Small and compact but plenty of power for 4 JBL speakers, fit where the factory amp was, 2014 Honda CRV EX-L, Has output to turn on your subwooker if you need it.

Pros: small and compact plenty of power

Cons: input wire harness to short.

Amazing clarity

Anonymous from Austin, TX on 3/26/2017

Crutchfield Customer Review (What's this?)

Wow what a difference in my 2017 crewmax Tundra. It really gives it an extra punch

Pros: Small and can put anywhere

Cons: Nothing

Slight power boost, and a bit of hum boost too

Anurag from Chicago, IL on 3/13/2017

As a part of my car stereo upgrade, I first went on to change the stock speakers to get a little boost to the low-ends (The mid and highs were good enough) The Polks I ordered made no difference to sound quality, so I went on and got the Alpine KTP-445U. After installation, I did not notice any boost to the lows. I then went on and replaced the Polks with the OEM speakers and that made all the difference. Contrary to what I expected, the OEM's despite their smaller magnets delivered a better punch with the Alpine power pack than with the high(er) end Polks. Overall, I am a (tad bit) more satisfied with the sound quality of my car's stereo with the Alpine KTP-445U installed. So why the 3 stars: The Alpine KTP-445U is an amplifier, and like (most) amplifiers, it will also increase noise. Not quite what I expected from an Alpine unit, but it is what it is. At low volumes, bass output is better as compared to the stock setup but at very low volumes the noise can be heard a bit, if you are my types with sharp (dog-like) ears. I got the unit installed by a pro, paid about a 100 bucks for the installation, but they did a good job at setting the gain. Check the Crutchfield Subwoofer Tuning article for some references you can use to set gain at the correct level Nevertheless, if you are looking to boost your existing setup without a sub, then the Alpine KTP-445U sure is a good way forward.

Pros: 1. Tiny little invisible unit, fits inside the dash 2. Slight boost your existing set-up, decent boost to the low-end frequencies

Cons: 1. Expect a slight hum from your speakers at low volumes, which is not noticeable at higher volumes

Alpine KTP-445U Power Pack

Adam from Las Vegas, NV on 3/12/2017

Crutchfield Customer Review (What's this?)

Would definatly recommend this amp if you're looking for something small that packs a decent punch

Pros: Small, good price and sound

Cons: None so far

Alpine KTP-445U Power Pack

Tom from Warwick, NY on 3/1/2017

Crutchfield Customer Review (What's this?)

Everyone at Crutchfield is AWESOME!! I love the sound after adding my new Alpine 4 channel amp. This was so small I was able to fit it in the dash behind the glove box, so I can easily access it for future adjustments. I installed this on my new Jeep Rubicon and what a difference!!! Thanks everyone @ Crutchfield another great job.

Pros: extremely easy install , and can pretty much hide it anywhere , very pleased with this purchase

Cons: I really don't have any !!

Keep looking...........

wyatt from Livingston, TX on 2/23/2017

Crutchfield Customer Review (What's this?)

Lot of noise and hiss....Lot of power, but a lot of hiss..Tried different grounding locations and every trick in the book and in the end, I switched to a Clarion brick amp...Big disappointment from such a big name...

Pros: Size

Cons: Too noisy....

Alpine KTP-445U Power Pack

Anonymous from Tampa, FL on 1/9/2017

Crutchfield Customer Review (What's this?)

Overall, I am very pleased with this purchase. I am surprised that when RCA jacks cannot be used, the solution is to cut the already short wires and extend them. A non-rca harness should be included with sufficient length.



One more please

Tom from Grant twsp, MI on 12/19/2016

Crutchfield Customer Review (What's this?)

This is the third ktp-445 amp I have purchased from Crutchfield, installed in boat car and truck. If your plan is simply to make significant upgrade to an existing sound system with stealth, space savings, and cost savings, you can't beat this amp. Inputs, auto turn on, adjustments, and reliability are the features I was looking for.



Alpine KTP-445U Power Pack

Anonymous from Huntingdon, PA on 12/13/2016

Crutchfield Customer Review (What's this?)

I installed this unit with the purchase of a new JVC head unit because after installing my Kicker speakers, I still didn't have clear sound. This little amp (really little) totally brought my speakers to life. I can now hear all of the instruments clearly. The best thing is that this amp is so small I was able to install it just behind the head unit without trouble!



Alpine KTP-445U Power Pack

Jonathan c from Okanagan, wa on 12/11/2016

Crutchfield Customer Review (What's this?)

Nice sounds good



Works well, easy solution

Anonymous from Marlboro, NJ on 11/28/2016

Crutchfield Customer Review (What's this?)

Definitely makes a significant difference. Driving JL C2 690tx (which were asleep with the aftermarket Pioneer HU) and JL C2 350x which were fine without an amp. Was able to fit it behind the stereo

Pros: Big difference in sound, works well powered from headunit power line. Easy solution if you don't want the hassle of installing an amp. Very happy with the sound.

Cons: Pricey for what it is, you are basically paying for convenience which is fine. The version that works with alpine headunits is cheaper

Magic in a box!

Rick from California on 11/20/2016

Crutchfield Customer Review (What's this?)

Love this small amplifier! I needed something to drive my JL C3s and this amp pushes them nicely! I'm used to the larger 4 channels from the past and this fit in my glove box

Pros: Small footprint yet powerful. You have to try this thing

Cons: I wish the exterior was a little fancier like the other Alpine models (LED lights)

Alpine KTP-445U Power Pack

Tim from Whittier, CA on 11/20/2016

Crutchfield Customer Review (What's this?)

Added to basic sound system in 2016 mustang gt it sounds really good now

Pros: Upgrades sound system fits behind dash nicely

Cons: None so far

Alpine KTP-445U Power Pack

Anonymous from Lebanon, PA on 11/14/2016

Crutchfield Customer Review (What's this?)

Easy install and sounds great!



Alpine KTP-445U Power Pack

Anonymous from Harpers Ferry, WV on 11/8/2016

Crutchfield Customer Review (What's this?)

Just what I needed to boost the volume.



Makes a big difference over stock head unit with aftermarket speakers

Anonymous from Columbus, OH on 11/7/2016

Crutchfield Customer Review (What's this?)

Brought a pair of JBL Stage 600Cs to life after the stock headunit in my 2016 HR-V couldn't cut it. I am amazed at the difference in quality and bass punch.



Alpine KTP-445U Power Pack

Vaughn from Alpine, TX on 10/28/2016

Crutchfield Customer Review (What's this?)

This is a great little amp. I mounted it on the ceiling of my glove box, and the cables were long enough to make it to the head.




Brian from Dedham, MA on 9/1/2016

Crutchfield Customer Review (What's this?)

I bought this amp to plus-up my stock stereo system in my 2012 Subaru Impreza. The sound was better after the installation, but the factory speakers were not good enough to handle the power.

Pros: better sound

Cons: needed to buy speakers (which i was eventually going to buy later this just sped up the purchase)

Does the job!

Douglas from Raleigh, NC on 8/25/2016

Crutchfield Customer Review (What's this?)

This amp is part of a complete audio system I put in my 2001 Jeep Cherokee XJ. I'm using it to bump up the power to four Polk Audio db651s speakers mounted in the stock locations. I set the cutoff at 60 and am running a RF Punch P300-10 for the bass. It has its own built-in amp. The Polk Audio speakers sound great so the amp must be doing something right. It's mounted behind the Kenwood Excelon KDC-X300 in the dash. Out of sight, out of mind.

Pros: Wiring was easy. It matched up nicely to the Kenwood harness and the vehicle adapter harnesses. Just a little head scratching, but it all worked out.

Cons: Got nothing. It works for me.

Great little amp!

TerryM from Luray, VA on 7/24/2016

This little amp packs quite a punch when you're short on mounting space. Going from stock head unit to an aftermarket always ends up sounding flat and tinny. I had purchased a larger amp to address this, however my plans to mount it under a seat ultimately turned me off. I bought this unit and installation was quite simple. No running wires from the engine bay and running a ground wire to somewhere on the floor. Just need RCA cables, radio wiring kit, and crimps. 90% of the installation prep was done before opening the car door. The size of this amp is great! It fits right behind my head unit with room to spare. I definitely recommend!




CP from Blackwood, NJ on 7/17/2016

This little alpine amp is Amazing! For the money and the convenience there is nothing out there that can compete. My piece of advice is use this amp bridged at 90 watts rms x 2. Using the 45 x 4 is ok for increasing clarity but will only give you a small power boost over your head unit. At 90x4 this amp comes alive and can compete with some bigger wired amps in power and clarity. I definitely recommend this amp for a small component set and it will bring it to life.

Pros: Definitive Clarity and power boost at 90w x 2.

Cons: 45 watts x 4 is just ok. I wouldn't buy this amp if I wasn't going to bridge it.

It has its pros in cons in my opinion.

audiophile from Grand Rapids, MI on 5/13/2016

This is definitely an improvement to a stock head unit. It sure does pack a punch after tapping into the stock head unit power and ground, as described in the manual. Some maybe skeptical that splicing into the head unit power will be sufficient for an amplifier but I think it supplies plenty of power. I replaced the stock speakers with JL audio C2 series and had the gain on this amplifier at nearly 20-25% and it was quite loud.

Pros: Small and fairly easy to install depending on your vehicle. Provides a good sound upgrade for a stock head unit, so you can keep the factory head unit and still have searing wheel controls with out purchasing extra hardware. Small size also makes it easier to install with the ability to mount it in the front of the vehicle without needing to run wire across the whole car.

Cons: -No power indicator light or over current light. Hard to tell when the amp is actually drawing power. -A low level line out would also be really nice. -The speaker wire with the white/brown stripe was extremely hard for me to find for some reason, it almost looks identical to the white/grey stripe.

Great amp for tight spots!

Thomas from NJ on 5/8/2016

Crutchfield Customer Review (What's this?)

I was replacing y 2002 WJ Grand Cherokee's Infinity radio, which meant I could not use the factory amp anymore. I was going to run the speakers off the Kenwood head unit- then I found this Universal Power-pack online. I patched it into the factory amp's wiring harness under the back seat, even re-used the factory power/ground wires. I ran two sets of 11.5 foot RCA cables for my signal from the Kenwood to the amp because I wanted a nice clean signal. I already had full range 6.5 speakers in the front doors (was not using the old stock dash speakers anymore). WOW it blows away the original amp, nice clear sound with enough bass to shake my seat (jazz/blues/rock) from the four 6.5's in the doors. I can't believe I didn't have to sacrifice cargo space or run huge wiring for it! Nobody even knows it's there- perfect!

Pros: Small size, easy and clean install (re-used factory amp harness), nice clean sound

Cons: None after a year and a half

Excellent value and quality

Mjm from Honolulu, HI on 5/7/2016

Crutchfield Customer Review (What's this?)

I researched small amplifiers for my jeep. I just wanted little more power to my aftermarket speakers. This is the amp if you want a boost to your factory or aftermarket radio.

Pros: Color coded wired for ease of installation of you are using aftermarket radio

Cons: Non so far

Works great!! helps a weak aftermarket deck with sound output

P Brokaw from Tacoma, WA on 5/4/2016

Crutchfield Customer Review (What's this?)

Installed in 2006 Wrangler. Put amp underneath steering column dash panel. Fits like a glove. Deck is a marine grade Sony media center and speakers a Rockford Fosgate 5 1/4s front and rear.




Matthew from Schuylerville, NY on 5/1/2016

alpine has gone down hill this amp is a pain 2 install gets really hot idk what happen with alpine but thay are junk now

Pros: none

Cons: 2 meny

Such a powerful amp for the compact dize.

Jerry from Ft Worth, TX on 4/10/2016

Crutchfield Customer Review (What's this?)

Excellent amp to my existing factory radio. My radio is 300% clear and loud with gain turned down to zero for my factory speakers.

Pros: Compact, easy to install in your dash console. Plug and play remote. Other words, I did not need to attach the remote wire.

Cons: None

I have a alpine 9425 &6×9 Rs nothing but awsome,Now its time to upgrad

David from Inkster, MI on 3/16/2016

I have loved my 9428 and 6×9 for about 10 yes. Time to HD149BT & 6×9R the processors are top notch have to get more, but Im on ssi so 1 peace at a time. Please never change. I will only buy Alpint. Thank you. Always wanted you cence I was a young boy. Thanks for all the great music.

Pros: No cons,it is best audio I haver heard in my life,a please dont make to many childish changes, like flickering lights this is not a toy factory, you dont make toasters or disco balls,you have the best processor's in the business. Dont screw it up ,like Sony did I the mid 90's,they have there fingers I to many things.Your doing great.I would love to buy a t shirt or hat.Love to show off Alpine,that's all I want. Thanks

Cons: No cons even after all this time,time now for the hd149bt&hopefully a bit more.But no cons here. Thank you

Great upgrade

Frank D from houston, TX on 3/12/2016

Easy install, fit in glove box, 4 channel amp improved the output of the Pioneer 4100NEX head unit with RCA plugs. After setting the optimal level gain, the sound was full and rich. Using Kicker aftermarket in front and rear.

Pros: Ease of install. No need for separate power supply. Rich sound gains.

Cons: Lower power output than larger amps.

Alpine KTP-445U Power Pack

Jason from Madelia, MN on 2/25/2016

Crutchfield Customer Review (What's this?)

This Alpine power pack rocks! It pushes way more power to my door speakers than my in dash receiver did and definitely makes a difference in sound quality. It's small and compact and actually mounted behind my double-din in dash receiver so it's a clean install and hidden. I this in my 2012 Chevy Colorado powering my 4 door speakers and I am definitely impressed with the difference this Alpine makes. If I had to purchase it again I would no doubt.

Pros: Powerful, compact, easy to mount in-dash behind the receiver. Buy one, you won't regret it. The only thing that will wipe the smile off your face after hearing the difference this thing makes is the powerful sound coming from your speakers melting your face. Haha.

Cons: I can't think of any yet, I've been happy with it since the install.

Small but powerful

2015 Toyota Tundra Crewmax from columbia, MD on 2/16/2016

Crutchfield Customer Review (What's this?)

Excellent sound

Pros: Small, easy to install kept factory head unit sounds great


Hum after install in 2015 Subaru Forester

BFC from Seattle, WA on 2/16/2016

Crutchfield Customer Review (What's this?)

Installed two different KTP-445u amps in my 2.5i Forester Premium with factory head unit CF625UM, (non-navigation, non-Harmon Kardon) and Subaru Kicker upgraded speakers- had a low steady hum in background thru speakers. Followed Alpine instructions to a "T" , tried wiring thru head unit power and ground as well as a separate fused power wire from battery and three different ground locations nearby amp location. Changing amp gains didn't eliminate hum. Amp inputs set at speaker level. Spent a lot of time troubleshooting to no avail. Doesn't seem to be a ground issue or wiring interference etc. Hum is loud enough to be annoying at low or no volume on radio /CD/USB. Other than that the sound was a noticeable improvement from factory- a bit of power boost and clarity. It may be this factory head unit using speaker level connection is just noisy when amped. Research on the web after this issue has found enough feedback on humming and hiss with this amp in Subaru's that I just want to put this out there fyi.


Cons: Low background hum after amp install

Super powerful

Juice from rockville, MD on 2/10/2016

Crutchfield Customer Review (What's this?)

Great amp, great price, super powerful. What more do you want

Pros: Power power power. Price is even better. Very slim you can put it anywhere

Cons: none

Great Amp

Clinton from janesville, WI on 1/25/2016

Crutchfield Customer Review (What's this?)

After changing out the speakers I didn't feel like there was that much of a change. Added this amp, it made the speakers come alive. It was easy to install and fit neatly behind my dash.

Pros: Small, easy to install. Gets louder then I would ever want to listen.

Cons: None

Powerful little punch

Martin from reedley, CA on 1/22/2016

Crutchfield Customer Review (What's this?)

Great for people who need an amp in a very small space (does not require a separate wire kit, it piggy backs on the receiver). It even fits behind the dash in most cases. It is also a great idea if you are adding new speakers in the door along with a new receiver and want more than what the receiver alone provides (usually less than 23watts)

Pros: very compact, better power than a new receiver alone

Cons: if you like bass you will have to add a separate sub (i recommend one that is compact, can fit under the seat and has a built in amp such as infinity BassLink SM)

2015 Ram 1500

Nick C from Texas on 1/22/2016

Crutchfield Customer Review (What's this?)

I purchased this product along with 6 Kicker speakers for my 2015 RAM 1500. I had this amplifier installed professionally and it was mounted inside the glove box of the truck so that I could adjust the gain controls if needed. The amplifier was wired directly to the factory HU (8 inch touch screen, no Alpine) but I can't comment on installation, only sound quality. The quality is AMAZING. I had to have researched the Power Pack for at least a year before finally making the purchase, and man was that a good call. I literally have the gain turned down to almost zero, and this bad boy rocks the house. Such a noticeable difference before and after. The Kicker speakers really opened up and sound great with NO distortion what so ever. Anybody looking to upgrade their factor HU on a new model vehicle, I highly recommend this product. One comment I will add, I had quite an annoying hiss and static from the speaker after this was set this up, which typically I hear is from a Ground issue. For my particular case, it was not. The gain was too high!! So if you hear static through the speakers, turn the gain down (counter clock wise) until it sounds crisp with no distortion.

Pros: Small size, Huge sound. Price. Compatibility with factory HU. Gain controls.

Cons: None, time to buy this Power Pack.

Nice, small power

MattO from North Carolina on 12/6/2015

Crutchfield Customer Review (What's this?)

I installed this in a 2008 Tundra. I removed the panel to which the glove box is attached and put this on the back side of it. It is out of sight but I can adjust the gain easily by looking under the glove box. I'm sure that description is clear as mud. It made the stock speakers really come alive. I almost didn't change the speakers out as planned because they sounded so good.



Alpine KTP-445U Power Pack

Anonymous from New Franklin, ohio on 11/23/2015

Crutchfield Customer Review (What's this?)

Nice unit, made a big difference

Pros: Small- easy installation-versital

Cons: None yet

Great solution

Pmen from Outer Banks, NC on 11/18/2015

Crutchfield Customer Review (What's this?)

Part of a three sided attack (door speakers, Subwoofer, amp) to improve upon the crappy Ford / Sony non DSP 700W setup in a late model F150 Screw. The input leads as pointed out many times, are very short. Since I wired them to the speaker line of the Sony amp under the center console, it wasn't that big a deal. Set the amp up as a 4 channel. The amp delivers very clean sound through aftermarket JBL coax's in the rear doors and Focal components in the front. One small complaint is that the Kicker soundstage subwoofer replacement under the back seat will not come on until the volume is up beyond 1/3 which is kind of loud for some. It would be nice if everything worked together, but that's another story. Not much help from Tech support. All in all, very compact and fits well under the center console. Delivers clean, much improved sound, in place of the crummy Sony amp.

Pros: Compact design. Clear quality sound.

Cons: Lame instructions. Leads too short.

Clean sound, substantial improvement

Karen from Tennessee on 11/9/2015

I originally tried the Clarion XC1410 with the factory head unit in my Tacoma (with all new speakers), but had some issues with functionality and sound quality. The unit was professionally installed here locally. We swapped it out for this Alpine unit, and the improvement in sound quality was substantial. The Alpine produces a much cleaner sound, with good dynamic range and a better sound stage. The Alpine unit has a gain control and crossover, and the S/N ratio is higher, resulting in less high frequency noise. This unit, combined with new Focal and JL Audio speakers, produces excellent sound quality.

Pros: Clean sound, more control capabilities


Alpine KTP-445U Power Pack

Anonymous from Pennsylvania on 10/6/2015

Crutchfield Customer Review (What's this?)

excellent speaker for the price

Pros: could have a little bit more bass


Great little amp for any application

Chris G from Illinois on 9/20/2015

I have used 1 of these amps in 2 different vehicles and it has been great in both! I installed one in a 2002 Jeep Wrangler with a Kenwood head unit, along with Alpine Type S speakers. It was a great boost in power to the speakers. I also upgraded the factory sub to a small Kicker 6 3/4" sub and powered with an MTX amp. High pass frequency settings on the KTP-445 work wonders! I also just recently used another KTP-445 in my 2016 Subaru Legacy and installed Focal components. Amazing difference! Speakers were installed first and the factory head unit was obviously not enough to give the speakers what they want. Installed the KTP-445 shortly after (within 4 days) and I am beyond pleased!

Pros: Small, Easy to install for anyone with basic car audio knowledge, Very versatile

Cons: None that I can find yet!

Great little amp for Stratoliner Deluxe

R H from Kansas on 9/6/2015

I needed a mini amp to fit inside of a Stratoliner Deluxe fairing. I looked at the Clarion, it is also a four channel but it is not brigeable. I only needed to channels and wanted that extra power. Fits perfectly. Wow, what a difference. The factory motorcycle amps are drastically underpowered for hi way use. If anyone wants to know how to do this upgrade, contact me.

Pros: Small, light, great power and sound.

Cons: I don't really care for having to dust off the RCA leads to use them formspeakers level inputs. It's not a problem, just seems like they could have supplied both inputs.

Nice amp

Josh from Ohio on 7/2/2015

Crutchfield Customer Review (What's this?)

I am happy with this amp. I have it installed in my 00 S10 regular cab. It is tucked in behind the radio & A/C controls. It fits in there great with both factory deck and aftermarket radio installed. I tapped into the extra aux/cig lighter port below the dash to power it. Perfect spot and is 15AMP rated. Power is enough for me. Anyone with a small standard cab pickup knows that space is at a premium and this small amp allows me external amp power while taking up no room behind the seats.

Pros: Great size. Bridgeable.

Cons: I wish that there were replacement harness for sale. To use the amps speaker level inputs, you have to cut off the RCA ends (i.e. if using factory radio) If you later wanted to use the amp with aftermarket radio, you would have some issues with not having the rca inputs.

Decent amp

Spicy mchaggis from Norfolk va on 7/1/2015

Crutchfield Customer Review (What's this?)

Nice little amp that you can tuck and hide away, the instructions are simple and install is simple. BTW you don't need a 12v turn on, unless your using the 12v remote turn on output. Goes good with alpine type a.

Pros: Simple install

Cons: Needs longer wires, the output wires should be twisted together to aid in install, a drill will do this for you though.

Great for stock HU

Eric from Illinois on 6/29/2015

This amp is installed in a 2004 Ford Freestar. I have the stick HU still in placed. With the help of Crutchfield I was able to ID the right wires. Taped into the HU power and ground. Took about 40ish mins to install. Really that was just cutting and stripping the wires. But once installed the sound improvement was very noticeable. I have Focal 5x7's up front. And Alpine 5x7's Type S in back. I say it made them clearer and cleaner. Got this amp from a friend for ($20) so all in all great deal. In the end its a great buy. Note* If you are using this with out a sub. As in my case. Remember to take off the HPF.

Pros: Easy install. Good improvements


Alpine Power Pack

Anonymous from Texas on 6/17/2015

Crutchfield Customer Review (What's this?)

Great little amp



Great Upgrade

Dennis from Iowa on 6/15/2015

Crutchfield Customer Review (What's this?)

Small compact and easy to put in even inside the fairing on my 2008 Road Glide. I could have used some direction on wiring in the power. Had to loosen my gas tank up to run the power wired.

Pros: Great amp with low distortion

Cons: Was a little difficult to wire the power.

Pushes out the sound. Compact

ScotM from California on 6/14/2015

Crutchfield Customer Review (What's this?)

Small size makes it easy to stash inside a crowded dashboard. Sounds great. Bold strong sound with no distortion.Great for upgrading your system without going broke.

Pros: Compact Delivers quality sound

Cons: You still need some knowledge of car wiring. It's not a simple "plug-it-in-and-go device."

great solution to no having to run an amp

steve-0 from omaha ne on 6/8/2015

Crutchfield Customer Review (What's this?)

Pushes the non factory speakers just about to RMS like I wanted. The brand name equals quality and that's what you get. It's compact hides well and isn't fighting for battery space against my dedicated mono amp. Speaking of, it keeps my mids and highs in perfect balance against my two 12' fosgate subs running at 800w rms each. It's a mighty little guy and met my expectations.

Pros: Space power frequently range and distortion specs

Cons: I'll have to get back to you on that. I've really tried to come up with something helpful on cons but so far there isn't any. OK they're not giving them away free?

Great sound system!

TS from USA on 6/5/2015

Crutchfield Customer Review (What's this?)

We replaced our factory equipment in our 2008 Toyota Tacoma with a JVC receiver, six JBL speakers, and an Alpine amp. It sounds amazing! We had it professionally installed and they said Crutchfield was always so good about including everything that makes their job easier. We even saved money on the installation because everything went together smoothly and was made to fit in our truck. The customer service staff at Crutchfield was VERY good at putting together a system specifically for our truck and took the time to make sure everything would work together to give us the best possible sound at our price point. When it comes time to get the subwoofer, we will be buying it, and any other electronics, from Crutchfield.

Pros: Great sound system!

Cons: none

Does the trick

Craig from Colorado on 5/22/2015

Crutchfield Customer Review (What's this?)

Easy to install if you have 15 amp fuse radio line. Does what it says it will.

Pros: small, Don't have to connect to battery

Cons: can get hot

Not as good as I was hoping

Manny from San Antonio,Texas on 4/18/2015

This amp is so small it will fit anywhere. Had it hid inside my dash next to my speedometer cluster. It gets hot w/o air circulation, never cut off though. I have all my amps set with SMD DD-1 so there is no distortion in my system. Bought this amp for my tweeters up front, have a Fosgate T1000 for my sub(NVX VCW122) and an NVX JAD800.4 for my Alpine Type R 6x9s and Crescendo 6.5s. This amp is probably best for factory stereos and not so much for aftermarket HUs. I have a Pioneer DEH-x8500BH headunit which distorts at vol 61, max vol is 62. I can't turn up this amp past 54 bcuz it distorts even when amp vol is at min, but I am using the speaker wires to hook it up so maybe that could be a reason. Either way it's a nice amp just not for my application.

Pros: it's Alpine, small fits anywhere, no need for running power/ground lines, only uses 15 amps instead of 40 or 50 amps, connects straight to stereo power line with 15 amp or higher fuse at fuse box

Cons: not the best for aftermarket stereos, speaker inputs are very short and don't reach far, amp get hot w/o air circulation, no veriable filters only set filters, no bass boost


Bryan M from Illinois on 4/16/2015

Crutchfield Customer Review (What's this?)

I installed this amp to the factory stereo on a 2013 Honda Accord LX. It took a bit of doing as Honda is not generous with the wiring under the dash. It was very tight. I spliced into the existing speaker wires which were only 18 gauge but so far, they seem to handle the power pretty well. As other reviewers have noted, the amp does not come with very long wires on one side so I had to delay the install until the next day so I could pick up some additional wire to expand the connections. I went direct to the battery for my 12V power source as the factory stereo only had a 10 amp fuse and this amp requires at least a 15 amp fuse to allow you to tie into the stereo's hot lead for power. For those of you installing this amp on an Accord, the pass through on the fire wall is hard to find. I said a prayer and stumbled across it. It is behind the brake pedal and a bit to the left. You have to cut some of the sound proofing material to reach the grommet. You can first locate it by sticking your hand behind the sound proofing material until you feel the grommet. Once you find it, you are not home-free. The opening passes through a frame member and exits after a 90 degree turn. You will need a flashlight to shine into the grommet hole and locate the exiting light under the hood down below the brake reservoir. Have fun. Once installed, the difference is huge! I have 6.5 inch Kenwoods in the front and 6.5 inch Kickers in the back. The Kickers take the extra power better!

Pros: Great sound! Compact and relatively easy to install for a novice. Contact Crutchfield for a wiring schematic for your specific vehicle. Makes the job easier.

Cons: Needs longer wiring

Big things do come in small packages

Anonymous from Opelika al on 4/14/2015

Crutchfield Customer Review (What's this?)

Thought I needed new speakers. All I needed was more juice.alpine all the way



Power Pack

Tim from Monroeville OH on 4/9/2015

Crutchfield Customer Review (What's this?)

This really improved the sound. Great service. I even called them on Easter with a question and it was answered right away. Thanks to my FORD dealer for telling me to call this company.

Pros: Way better than factory crap they put in it now.

Cons: Takes a little time to do all the wiring but worth it.

Great purchase

JeremyD from Kansas on 4/6/2015

Crutchfield Customer Review (What's this?)

Was greatly impressed by the quality of such a small package. Fit back up under dash no issues find it a home. Wires all all color coded to match nicely. I didn't use the RCA portions I cut them off to eliminate a ton of extra wiring. If your patient and wire it up it's easy. Like not having to install amp kit.

Pros: Great little amp to power speakers using factory wiring.

Cons: Should have spent the extra money to purchase a alpine head unit so that everything just plugged in instead of all the wire connections. The amp would be cheaper this way but woulda had to spend extra cash to get the alpine head unit i wanted with features I wanted. Lessen learned on my side.

Very impressive.

Mac_will2 from Wichita, Kansas on 4/2/2015

I purchase this amplifier to increase the mids ,highs, in my head deck and I totally noticed a Enormous impact on how my front and rear speakers perform. With the 2000 watt amplifier in my trunk on my subwoofers, everything just connects together almost like meeting your date for the very first time.

Pros: A smaller unit with a greater impact.

Cons: Nothing.

Works good

GMeyers from Illinois on 3/29/2015

Crutchfield Customer Review (What's this?)

Lots of power in a small area

Pros: Compact Strong Power


Good way to go when you don't have $$$$

JT from Georgia on 3/23/2015

Crutchfield Customer Review (What's this?)

A solid piece of equipment to give you the small boost necessary to make your factory stereo sound less anemic.

Pros: Gives necessary boost to wattage w/o having to replace the entire system


The first and the best

Isaac from Wisconsin on 3/10/2015

The first mini-amp that was worth a darn, in my opinion. This little fella has been used on many installs where we weren't looking for full 4ch amp power. At 45wrms it's a touch overrated, based on the old meter, but it really breathes life into some starving speakers vs 20wrms or so that headunits put out. With the ability to be bridged to a 2ch @ 4O output, too, it's very versatile (keeping a honda factory sub working, ya dig!). Most recently I used it to spank on some 120wrms Morel Tempo Ultras, and it got them moving well. Can't recommend this thing enough. The only, only downfall is that it's not waterproof, so if it goes in a Harley fairing don't blast it with water.

Pros: Small, versatile, powerful, affordable. A no-brainer upgrade to any system where some new speakers aren't being powered to their full potential but you don't want to mess with a fullsize 4ch amp.

Cons: Not waterproof

Great amp

WRX owner from Nevada on 1/7/2015

Crutchfield Customer Review (What's this?)

This amp fit in the dash of my 2004 WRX behind the glove box. Using some weatherstrip foam and zip ties it attaches to a horizontal tube found in the dash of Subaru's. The weatherstrip went between the metal tube and amp it cushions the amp from vibration and helped hold it in place. I find that I often use most of the power this amp provides. In hindsight, I would have bought more efficient speakers in the front doors.

Pros: 3-4 times the power of deck with no hassles locating the amp or powering it. Just what I needed.

Cons: None

Great things to come

super soobie fxt from ny on 12/28/2014

I'm doing a tablet install on 2012 forester xt touring and this little gem will be my speaker driver. Looks well built and the wiring harnesses are really plug and play .... I bought the Metra wiring kit and like how the radio power can power this up ... Go me.

Pros: Small . meets the basics for amplifier

Cons: Needs a subwoofer companion

Nice Little Unit but Short on Help

SYates from Orlando, FL on 12/14/2014

Crutchfield Customer Review (What's this?)

I bought a 2014 Accord Sport with the understanding it had a basic head unit and low end speakers. I started by upgrading to some Blaupunkt Blue Magic speakers but the head unit is so bad, it could not push any sound through the speakers so I did some research and landed on this little unit. I will say I had some trouble with the settings. For some reason, I have to turn the gain completely off because otherwise it will cause the amp to kind surge through the speakers and the whole car vibrates. It took me some time to figure that out and is really the only reason I dropped a star on it. I am no stereo expert but I am no novice either so I was surprised at how little information there was available to help me troubleshoot. Thankfully the staff at Crutchfield was patient with my questions. The speakers sound great and it still gets plenty loud. I will not win any car stereo competitions, but it is so much better than the factory stereo and I am enjoying my music one again!

Pros: Small, compact unit that does a great job for the average install.

Cons: Not a lot of tech support or information. Also, I found the input harness that comes will it a tad short. I had zero clearance with my factory stereo and it was tight work back there and the short harness did me no favors. I got it to work, but not with out some effort.

Great little amp for the price

xJoeMama78 from Chandler, AZ on 12/9/2014

Crutchfield Customer Review (What's this?)

I purchased this amp to power a pair of Focal 165VRs in a 2015 Forester. I wanted to keep the system upgrades simple and had heard that the power wire to the factory head unit was sufficient to power this amp. I wasn't looking for the ability to play music at really high volumes, but just wanted to provide the Focals with more than factory head unit power to increase clarity and for it to be audible with all of the windows down and the moonroof open while on the highway. This amp delivered everything it promised. It is small enough to fit behind the dash and the head unit power and ground were sufficient so I did not need to run a separate power wire. My head unit does not have RCA outputs and I did not want to cut off the female RCA connectors from the Alpine harness so I simply added male RCA connectors to the front speaker outputs from the head unit. I followed the instructions to set the amp into 2 channel mode and connected the appropriate amp speaker outputs to run the speakers bridged. The instructions were clear and it was easy to install, setup, and tune. Overall the amp sounds great. It is not going to be as clean or loud as a more expensive, high end amp, but for the price it is great. Now volume level 10 on the head unit is louder than it used to be at volume level 30. Volume level 10 is sufficient to hear music on the highway with all of the windows open. The amp distorts at higher volume levels but only after the volume is too loud to be comfortable.

Pros: Small size that can fit behind many dashes or in a glove box. Low enough power requirements that it may be able to be powered by the factory head unit power wire. Sufficient clarity and power for the price and size.

Cons: No high level input harness. High level input is possible but you have to cut off the female RCA connectors. This itself isn't an issue but the instructions don't mention which wire is positive and which is negative, and this could be an issue for someone without experience. Trade-off between value and size. There are amps that provide more power and are cleaner for the same price, but they are all much bigger.

Alpine KTP-445U Power Pack

Cliff from Arizona on 12/3/2014

Crutchfield Customer Review (What's this?)

Compact power pack. Easy to mount under the dash




Anonymous from Bardstown, KY on 11/24/2014

Crutchfield Customer Review (What's this?)

This little box has some kick. I have it on 2 6x8's and 2 6" I think in my Ram. Oops...blew one of the rears. Looks like I'll have to replace soon because the rattle is nerve wracking. I only have the gain at half or barely past...I guess I need to make sure they can handle it.

Pros: Great power at a decent price. Use with any radio? That's thumbs up!

Cons: Make sure your speakers can handle it.

love it, exactly what I needed, but READ MY CONs

tom from Denver, CO on 11/10/2014

Crutchfield Customer Review (What's this?)

Great little amp, not too difficult to install, makes a noticeable improvement in the sound quality of my aftermarket speakers. Read my comment in the Cons. I would actually give this amp 5 stars, but I want to draw attention to this error.

Pros: small enough to fit behind dash, just enough power so that i don't have to replace speaker wires

Cons: The diagram explaining the switches in the instruction booklet and the diagram printed on the amp are conflicting... since one was printed in black ink on a white background and one the inverse, it leaves the one on the amp telling you the opposite of the switch selections, meaning if you follow the instructions, you'd have your crossover set up incorrectly and you'd probably think the amp was worthless. Some of these negative reviews make me think that's exactly what happened.

Just what my Harley needed

John from Chesterfield, VA on 10/3/2014

I put a Kenwood KMR D558BT on my 2011 Harley Street Glide along with Hogtunes 5.25" fairing speakers and Polk Audio DB691 6X9 speakers in the saddlebag lids. I was hoping that the 22W RMS power the Kenwood pushed would be enough to push this setup since I'm not looking for thunderous bass just good clear sound at highway speeds. Well that setup sounded great in my garage but once on the highway I had to pump it up all the way past 30 of 35 on the volume and it sounded very shallow and a little distorted. I saw this amp at the store and I loved the small size for an easy add on under my fairing were space is limited. Setup was easy if you can follow directions. After installation...WOW WHAT A DIFFERENCE!. It really gives the system depth and clarity. At highway speeds it sounds awesome. Now at 30 of 35 volume I can't hear myself scream. I have the gain set at about 11 o'clock so it doesn't clip. You can hear all the notes so clearly. I couldn't be happier. It's doesn't have super bass but that is because I don't have a sub. This is for someone that just wants good, clear, deep sound. Don't knock it because it doesn't do what a larger amp does, it's not supposed to. Get the right size amp for the job you need it to do.

Pros: Small size Easy installation Great sound

Cons: None, it does what I asked of it.

Great factory amp upgrade

schambo from Bergen County, NJ on 9/22/2014

Crutchfield Customer Review (What's this?)

If you want to keep your factory head unit this is the answer. Doubles the power output and is simple to install. I have been using it for over 8 months with Infinity Reference components and it sounds even better as time goes by. For me it is almost too much volume. It's not going to blow your doors off but will satisfy your needs.

Pros: Good power output. Compact size allows for install in tight locations. Built in selectable crossovers let you adjust for best speaker response. Can double power for 2 channel output.

Cons: None as of right now.

Big bang in tiny package

phaelax from ohio on 9/17/2014

My application was a little different than the average user as the car was a '73 Duster. I did not want to cut into the factory dash to fit an aftermarket radio nor have one hang from under the dash like you commonly see in old cars. This tiny amp easily fits behind the dash. I made a custom harness to use an 1/8" audio jack for the input source which I fit into a pre-existing hole where an old radio knob used to be. Using my iphone for music instead of a head unit, this little amp is enough to power the rear 6x9s loud enough (and without distortion) to actually hear the music over the thundering rumble of the 440 block, which is nice on longer highway trips. Only thing I wish it had was an external line to control the volume rather than the dials on the amp itself. I'd rather be able to adjust the volume from a knob than on my phone.

Pros: Small size, clean sound

Cons: No remote volume

Super power pack

Bob L from Cranston, RI on 9/12/2014

Crutchfield Customer Review (What's this?)

Unbelievable compliment to any stereo. I put this in my Harley Road Glide. Had Kenwood stereo with Kicker speakers installed without it at first and when riding I had to crank the stereo. after about 15 minutes, the speakers started to cut out. I thought I had inferior speakers. After talking to awesome tech support, they told me to buy this amp. the radio could not handle being maxed out that long. Once installed, which was super easy, I was blown away with the results. I would not install another radio without this must needed add on. Again, cudos for tech support

Pros: small compact size, fit great in motorcycle fairing. Just enough power for a great price

Cons: Sorry, don't have any

Alpine KTP-445U Power Pack

Joe from Wesley Chapel FL on 9/5/2014

Crutchfield Customer Review (What's this?)

I installed this in a F-150 Out standing little amp. Easy to wire up and fit right behind my H/U with some zip ties no crazy amp wiring . If you are like me and are looking for great sound quality this power pack will bring out every little sound. Here is a tip the RCA jacks are female and if you get a new H/U like I did the jacks on the back of that are female get some adaptors when you order or just get some RCA wire because the one that come with it are only about 4 inches. I was in the middle of the job I just cut off the RCA and just wired it up to the harness.

Pros: GREAT SOUND QUALITY Small size / easy to hide Wiring was very easy Crutchfield did help

Cons: Setting switches a little tricky RCA to short

Alpine KTP-445U Power Pack

James from Hilton Head Island, SC on 8/24/2014

Crutchfield Customer Review (What's this?)

It is an okay amp and does what it promises. You can definitely hear the power boost right away. So that's good and don't mistake me. But it leaves me a little wanting as it quickly reaches max gain without distortion. Then the sounds become tinny and you have to back off. I've had mine about 3 weeks. I want a full 75 RMS and this isn't enough for me. And it doesn't' generate more power at 2 ohms. It's all right if you know you aren't going to want more, but I'm going to be ditching mine and getting a regular 75 watt per channel 4 channel AB amp for about a Franklin more. It is supposed to fit up under behind your head unit or someplace else close, and it does, barely finds enough room there. It attaches easily to the cigarette lighter power and ground in the dash with a tap connector. That's the best part. Also, I've had my two regular AB Alpine V12 amps go out on me recently. So I'm not too high on Alpine right now.

Pros: Ease of connection. Just barely fits behind the head unit.

Cons: Reaches max gain quickly and leaves me wanting for more. It's great if you aren't into the big time.

a little more juice

Stan from michigan on 8/12/2014

Crutchfield Customer Review (What's this?)

I have added aftermarket speakera to my doors and dash and they were sucking the juice right out of my cd player. i hooked this little guy up and and now it sounds better than ever and has power left over.

Pros: compact, works great, good quality manufacturing


Awsume Amp

Mack from LaGrange, IN on 7/8/2014

Crutchfield Customer Review (What's this?)

Totally made my speakers come alive!

Pros: Compact size fit behind my stock head unit!

Cons: none

2011 gmc sierra extended cab

Scott from Ky on 6/30/2014

Crutchfield Customer Review (What's this?)

Awesome little amp , installed it with factory unit with some alpine 6-1/4.

Pros: Small, compact ,and a lot of power , different crossover points on amp a plus . Truck rocks now , need to add subs. Crutchfield customer service provided all the schematics on the wiring diagram. Overall good amp .

Cons: Definitely not a plug and play , didn't like having to cut into factory wiring harness . If you have any experience in installing radios should be fine , was time consuming and had to lengthen speaker wires after cutting RCA 's off .

That added punch

RMJ from Fredericksburg,VA on 6/24/2014

This amp gives my system that added punch that makes the tunes blast.

Pros: Awesome little amp

Cons: Nothing

Nice little Amp (2nd review)

Juan on 6/16/2014

Please read my previous comments of this amplifier for a more in-depth review of this product. After removing the power wire that ran from the amplifier and piggybacked off of the head unit. I decided to run the wire directly to the vehicles battery by simply piggybacking off the 8 gauge wire that ran to the amplifier powering my subs and this amplifier no longer suffers from clipping much better performance with the gaines adjusted at the 1 o'clock position

Pros: Clean sound, better base and super tiny

Cons: Running this Amp to the head units power supply doesn't work if you like it loud (must have its own power wire from the battery) despite what the instructions tell you!

works well

Anonymous from st. peters, mo on 6/14/2014

Crutchfield Customer Review (What's this?)

Paired this with a new Kenwood kdc-x598 and my older polk speakers in my fox mustang so that I could even be able to hear my stereo over my loud exhaust at cruise speed, but didn't want to have to mount it back near my sub and amp that I have setup for quick removal on track day. Was easy to wire up, plenty of extra wire in the harness to put it just about anywhere in the dash (and small enough too), used the rca inputs, and it sounds really good even without messing with the gain settings on the amp. I just used some strong velcro to mount it on the floor behind the reciever. Gives enough power to actually get clean mids and highs with the windows down at speed (bass was never a problem).

Pros: Easy install, compact size, good power for a small amp


Nice Boost and stays hidden

Hit the road from Moreno Valley, CA on 6/13/2014

Crutchfield Customer Review (What's this?)

It was nice to fit inside the dash and gave my speakers some more boost especially the bass.

Pros: Nice and small. More Kick.

Cons: Putting all the wires together.

Great little AMP!

Rob H. from Milner, GA on 6/3/2014

Crutchfield Customer Review (What's this?)

Great little AMP sounds great, easy to install and hide, would give it 5 starts however I had issues using my Infinity speakers rated at 3 ohms, amp kept going into protect, worked with the tech team and found that to be my issue so if your speakers are not rated at 4 ohms buy the Universal but great product!

Pros: Easy to install and sounds great!

Cons: Does not work on 2 ohm speakers

Small package big quality

Harley rider from Chickasha, OK on 5/31/2014

I installed this in my 2012 Streetglide in less than an hour. Amazing difference. It sets easily on top of stereo inside fairing. I had already upgrade the factory speakers so adding the amp gave me great sound and plenty of power left over if I decide to put speakers in my bags. Highly recommend for bikes

Pros: Small, easy to install, good quality

Cons: None

Alpine KTP-445U

John from Northeast Ohio on 5/27/2014

Crutchfield Customer Review (What's this?)

I purchased this a while back to install in an Impreza. I finally got around to that and I am very satisfied with the improvement in sound volume and clarity. A very compact unit that delivers well for its price point. It is also easy to conceal. I would highly recommend this unit to those looking for a little more power in a package that will not take away from space. Others have complained of the poor instructions. I didn't have any trouble understanding the wiring or switch settings. Everything worked right the first time. If you understand wiring diagrams and color codes, this should be no problem.

Pros: Small, good value, sounds great.

Cons: none

The little amp that could...

MisterMike559 from Sanger CA on 5/3/2014

Crutchfield Customer Review (What's this?)

You can not go wrong with one of these Alpine amplifiers. Whether, you go with the plug-n-play(KTP-445A) model, or the universal model; like the this one. This is the one to get, if you are not using a Alpine head unit, or a head unit that is not plug-n-play compatible. I started off with the the KTP-445A for my front and rear speakers since I have a Alpne CDE-147BT head unit. Sounded clean; and loud. But I was missing the sound imaging I was looking for. I finally added kick panels with components to tie up the mid, and high's in my system. I used this universal model amplifier to send the power to the kicks, via RCA cables. Wasn't sure if I was able to run both models, but a quick response from Crutchfield, reassured me it was possible. Wow, all I can say. Components in the doors and kick panels are the same Alpine models, but now; the system sounds so much louder. Sound imaging sounds so much more equal now. You can't go wrong with these amps. So compact, and simple to use. Hardest part was finding a place to place these. An with the size that they are, it didn't take long. When picking up this amp, get a 8 gauge amp kit, and some good quality RCA cables. Crutchfield can help you out, if you are not sure which ones to get. Make sure to set gain levels properly. That way you optimize this amplifier, and prevent any noise interference. The internet is your friend, when you don't know how to set amplifier gains.

Pros: Compact Low power consumption Adjustment on crossover points 2-4 channel setup

Cons: Requires a 8 guage amp kit. Con, only if you are not ready to run power wire from battery to cab. Setting gain too high can pickup noise. Setting gain to match head unit signal is vital in making sure you don't any noise.

Powerful little amplifier

White Wolf from Arlington, TX on 4/28/2014

Crutchfield Customer Review (What's this?)

Small enough to fit in my fairing but powerful enough to hear at 100+mph. I am extremely pleased with this amp.

Pros: Small, powerful, easy to connect.

Cons: Dip switches underneath for settings.

Small amp, just right power

Jason from Portland, OR on 3/28/2014

Crutchfield Customer Review (What's this?)

Works as it is supposed to. Easy install. Fits in nicely under my glove compartment.

Pros: Small, easy to install.

Cons: None that i encountered.

Big improvement, Small Package!

Russ from AR on 3/4/2014

Crutchfield Customer Review (What's this?)

Bought this along with a Kenwood head unit to replace factory Silverado radio. I listened to the new door speaker I bought on just a head unit then on a small amp so I knew I wanted a bit more power. This little amp really livened up the JL Audio's in the truck! Easy install and sounds awesome! Called Mike at customer service with some concerns about not wiring straight to the battery but with his assurance that my trucks power wire was enough I went with the install as per instructions and have had no problems with clipping or distortion. I have an 18 year old son and he was amazed at the difference this little amp made to balance out the system!

Pros: Very Small, runs off head unit power at full tilt with no problems! Great improvement over running just head unit power, really brightens up good speakers.


Deceiving Little Amp

manooti from east stroudsburg PA on 1/21/2014

Crutchfield Customer Review (What's this?)

Installed this amp with a new hu from Crutchfield. It is powering the stock speakers in a 2006 Passat B6. All I can say is w.o.w. I expected clarity and got both ear bleeding volume and clarity. The amp is tucked in the glove box and still stays cool to the touch. Have no problems with install except the tiny little xover switches under the amp. Had to use a fine flat head. Next test is how they run components after my stock speakers blow. >:)

Pros: Wires are thick. Thicker than a new head unit from pioneer. Long leads. Stays cool due to class d. Front and rear crossover and gain control. Can be bridged in 2 channel mode for more power. Sounds awesome.

Cons: Amp is nice but not when it needs its own power cable when radio fuse is under 15a. At this price, and then running power cable, might as well pick up a stronger amp. It is good if you know it will work for you. Also have a very slight hiss/hum with no audio. Lower gain, less hum but still there. Will not run power cable and use separate ground as it defeats the purpose of this amp. Crossover controls are too tiny to switch. Need a hobby flat head screw driver or a knife.


BJK from OKC on 1/18/2014




Nice little Amp but not if your using component speaker set up

Juan from Chicago Heights on 12/20/2013

Nice little Amp if you want a cleaner sounding system and can afford an expensive amplifier or simply don't want to bother with installing one.... I installed this Amp in a 2006 impala with a set of Kicker components in the front and Kicker 6x9's in the rear using my RCA 5 Volt preouts from my double din eclipse deck ... Its not much louder than the head units amplifier but it will deliver deeper bass and crisper highs at a lower distortion rate, but if you turn up the volume to high for to long, this little Amp will CLIP!!! At least it does with my set up... I'm gonna try supplying a better fused power wire directly from the battery to see if it solves my problem and if that doesn't work than I'll turn down the gains on the amp... However the gains were adjusted using the method described in the instructions (standard method of adjusting gains)... I hope something works, otherwise I'm taking it out and running a real external amplifier.. To bad too because it sounds very good, I've NEVER had an amplifier clip at non-distorted volume levels, so I'm really hoping that piggybacking off the head units power wire is the problem


Cons: Not Recommended if you like your music loud... This Amp will clip at high volumes

Big sound in a little package

B-RAD from Indianapolis, IN on 11/22/2013

Crutchfield Customer Review (What's this?)

This is a great solution for some who wants a simple solution to add some kick to your factory installed stereo.

Pros: easy to install, small enough to fit behind your radio in the dash. Great company in Alpine and not alot of money for what you get.



Kevin from Arcadia,WI on 11/12/2013

Crutchfield Customer Review (What's this?)

Excellent and affordable upgrade from factory system. Paired with 4 Infinity Kappa 62.11i speakers and they sound great.

Pros: Crutchfield customer service is the best

Cons: None

Great amp

Butchie from Washington on 11/12/2013

Crutchfield Customer Review (What's this?)

Great little add-on amp. I am playing this in my boat, so power consumption was a concern.....don't want to run down the batteries while at anchor in a remote harbor. My existing Bose161 speakers sound much better and the added base far better than before. I especially like the output control screws for front and rear channels, which allows for setting the initial balance between channels. The plug and play convince is great!

Pros: Good sound, easy connections

Cons: None

Alpine KTP - 4450

Tim K from Sanford, NC on 11/6/2013

Crutchfield Customer Review (What's this?)

I have a 14 year old GMC Sierra Z71 truck and the factory stereo system finally bit the dust. Called Crutchfield for guidence and recommendations for replacing all of the factory equipment. I was a little apprehensive in purchasing this amp because of its size, but truly pleased I purchased it. There is noticeable difference with it and a really great product to be so small. The ol' truck sounds great now and extremely pleased with the performance. It is also very easy to store with its size. If your looking for a boost in your system this little amp does a great job.

Pros: Sounds great, easy to install, compact size

Cons: none

alpine amp

Anonymous from metairie la on 10/29/2013

Crutchfield Customer Review (What's this?)

I bridged it down to 2 channel's & have it running a pair of focal coaxial & its soundd great plus with it small size it fit it the dash

Pros: great product



CalN from Bloomington, MN on 10/27/2013

Crutchfield Customer Review (What's this?)

Wow, what a great little amp! I found the amp very easy to install and easy to adjust the gain etc per the factory instruction sheet(well written by the way)and a big plus is that it is so small it fit behind my Pioneer double din deck in my dash. The clarity and volume that it gives to my 4 Polk speakers is excellent, it really brings out the fullness of the low end in my 6X9's. This little amp is so worth the money and I am very happy I decided to get it!

Pros: small size, easy to install(if you have a 15 amp or greater fuse), very easy to set up

Cons: absolutely none

Mighty little amp!

Mike K. from Chicago area on 10/23/2013

Crutchfield Customer Review (What's this?)

What a great compact amp. I bought a 2013 Santa Fe and I wanted to keep several features made available to me through my stock stereo and I did not want to change the cosmetic look of the vehicles interior by swapping stereo heads. Having said that my stock stereo had no bass and lousy volume and I knew a stereo upgrade of some kind was in my near future. I turned to Crutchfield for advice and this amp was recommended to me. It sounded like exactly what I was looking for so I made the purchase and installed it myself. This amp made the difference I was looking for and I could not be happier. I want to mention that the compact size of this amp made it very easy to stash inside the dash board. If I ever need to gain access it all I have to do is remove the passenger side AC vent and it is right there. This is a mighty little amp that makes BIG sound! Add the Kicker speakers and you have a great system!

Pros: compact size, ease of installation, big sound

Cons: none

great amp

Anonymous from Altoona, PA on 10/20/2013

Crutchfield Customer Review (What's this?)

Great amp really makes my system shine now installed behind my head unit with a little modification and makes a huge difference with my polk speakers you won't be disappointed if you buy



Good product

ch from kentucky on 9/30/2013

Crutchfield Customer Review (What's this?)

product works well enough for what i wanted to do. I can't complain about it. I merely couldn't hear the radio when the Jeep top was down, and it boosts enough for me to hear now. Eventually i will get some higher end speakers and a sub to make it a bit better sounding.



Alpine KTP-445U Power Pack

wortman from gaston, sc on 9/16/2013

Crutchfield Customer Review (What's this?)

The little amp that could and will

Pros: small, light, easy power hook up, clear!

Cons: cant think of any unless you are hearing impaired and need much more power.


Jon from San Diego, CA on 8/23/2013

Crutchfield Customer Review (What's this?)

Like others have said, this amp has RIDICULOUSLY short input wires, which just makes it impossible to install. Do yourself a favor and either buy extra RCA cables if you're going to be using an aftermarket deck, or use long speaker wire to make the input wires longer. I spent about an hour connecting everything with the short wires, then discovered when I wanted to put everything back together I couldn't get the amp to fit anywhere because the wires were sooo short. I have a ford edge and there's plenty of room behind the dash too. Like I said, just do yourself a favor and lengthen all the input wires, and you can also map out all of the color connections to your specific stereo while you do this as well, it will save you TONS of time. As for how it improves the sound, there is a definite noticable amplification of sound with this installed. I upgraded my speakers first, added a sub, and then about 2 weeks later installed this power pack, and it does make a huge difference. I had to turn the gains all the way down and I still feel like I get a little distortion at higher levels so I wish you could turn it down even more, but maybe my Ford head unit just puts out of a lot of voltage or something...not sure. I have it set with 120hz HPF and it definitely helps my 5x7 speakers with distortion, the sub takes care of anything below this. I tried 80hz and it didn't sound right, I kind of wish there was a 100hz setting but I can't sounds a LOT better.

Pros: Small, space saving, no need to rewire your car.

Cons: INCREDIBLY SHORT INPUT WIRES, you MUST lengthen them if you want to move this anywhere and have access to it! Also, it's not a very straight forward install -- if you have never done car stereo stuff, I would just take it to a shop and have them do it. No 100hz setting, only 60/80/120

Boom boom

Super fish from West michigan on 8/17/2013

Crutchfield Customer Review (What's this?)

I love the size of the unit, the power output is awesome and the size allows me to stick it under my front seat which is great. Perfect for what I needed for I love Alpine.

Pros: Size, power output, ease of hooking up

Cons: I wish I had stronger power output maybe 100 Watts so I could run a sub.


John from Bethany Ok on 8/11/2013

I bought this amp to clean up the power to my factory speakers in my 91 Dodge van, and it did that with gusto! The sound from my stock speakers is great now,for what they are. I can not wait to upgrade the speakers to Alpine Type S next !

Pros: Easy to install Clean sound

Cons: none yet

good amp in jeep jk

Anonymous from GA on 8/10/2013

Crutchfield Customer Review (What's this?)

Easy to install except the wires are too short. Used speaker-level lines for the connections. Good improvement in clarity for driving with the top down.



focus amp mini

tutman from michigan on 7/16/2013

Crutchfield Customer Review (What's this?)

nice compact size. crutchfield recommended this using my stock car wiring. they matched me up with some polk speakers that works very well. the sound rips!!! i decided to keep my stock radio with the cd player and still sounds great. this little amp pounds those speakers and sounds great. just make sure you get the correct speakers, crudchfield will advice you on the crooect stuff.

Pros: small size, was able 2 install it behind the radio with some zip ties

Cons: speaker inpit wires were 2 short, had 2 splice them with longer wires than splice that 2 the radio. just a little bit of extra work is all.

Alpine KTP-445U

Justin S from Indianapolis, IN on 7/14/2013

Crutchfield Customer Review (What's this?)

Great power for the size, quick and easy to install. The instructions were fine (not rocket science). I tried to adjust the built-in crossover and didn't hear much of a difference. My stereo sounds great, its crisp and clear while interstate driving with the windows down :)

Pros: Size, easy to stash away almost anywhere.

Cons: Careful where you put the amp, it gets hot! I'm considering relocating the amp with fan to cool it. Currently, my daily commute is 20 min. each way so not too worried about prolonged heating yet.

Clean power - but use the RCA level inputs!

PatrickM from Plano, TX on 6/29/2013

Crutchfield Customer Review (What's this?)

This unit was recommended to me by a Crutchfield advisor. The head unit in my system is a Kenwood KDC-X997. When I installed it, I used the speaker-level inputs and clipped off the RCA connectors and set the amp's jumpers. per the instructions included with the amp. With the gain trims set at halfway, the sound was screaming with the head unit level at only 10. I have an Infinity BassLink sub connected to the Kenwood's sub outs, and there was no sound coming out of the sub. The culprit: the sub-out signal from the head unit was simply not strong enough to drive the powered sub. The solution: turned both gain trims on the Alpin amp to minimum which then allowed the head unit to be turned up enough to get a good signal to the sub.

Pros: Clean power and clarity.

Cons: Make sure you use the RCA-level inputs on the amp

Great Sound Poor Instructions

JimB from Lake Stevens, WA on 6/20/2013

Crutchfield Customer Review (What's this?)

This little amp pumps out the power and really makes the receiver sound great!

Pros: Great power and clean sound!

Cons: The instructions are horrible! I had to call Crutchfield for help for the first time ever and blowing 4 fuses. The tech was great and got the stereo and amp running in a matter of minutes!

Perfect Power Booster for Jeep Wrangler

Josh from Vail, AZ on 6/17/2013

Crutchfield Customer Review (What's this?)

If you are looking for a mild power boost that can be mounted out of sight behind the dash (at least in a 1997 Jeep Wrangler), this is an excellent option. My Wrangler looks like it has the original factory sound system, but it sure doesn't sound like it anymore!

Pros: Compact (should fit behind dash) Noticeable improvement in sound

Cons: Mild power boost May require running a separate line to the battery (1997 Jeep Wrangler only has 10A fuse on receiver circuit)

The Perfect Choice

RobertP from Clemmons, NC on 6/8/2013

Crutchfield Customer Review (What's this?)

The Alpine KTP-445U Power Pack was suggested by a Crutchfield salesperson as the one that would accomplish my goals of more power and cleaner sound. I would be installing it between a Pioneer DEH-X6500BT receiver and 4 Polk Audio DXi650 speakers, replacing the factory installed system in my 2008 Toyota Matrix. For my type of listening, it was the right choice. The sound is powerful and clear, but not overbearing. Installation was easy, using the straps provided with the unit, even though I had to adapt the unit to fit my particular situation. By using the StreetWires Zero Noise 5 Stereo Patch Cables that I purchased, the amp is proving to be exactly what I wanted.

Pros: Compact size, clean sound, and powerful enough for most standard applications.

Cons: None

Great upgrade

tomg from WI on 6/3/2013

Crutchfield Customer Review (What's this?)

Great product, what an improvement from before. Very easy to install.

Pros: compact size

Cons: none

Little big amp

Boz from Blue Ridge Summit, PA on 5/21/2013

Crutchfield Customer Review (What's this?)

A mighty mite. Good enough power to wake up most and quartet of speakers. Currently pushing a pair of Alpine Type R components and some soon to be replaced Polk db's. Yes , it makes the Polks cry. But the Alpines ROCK! I needed a good compact amp and this fit the bill perfectly. It allowed me to mount a 4 channel amp AND a monoblock amp in a very small space.

Pros: Powerful, small, ease of use.

Cons: A bit salty for its size/power.

WOW!!! Truly amazed!!!

chaces1 from NYC on 5/16/2013

Crutchfield Customer Review (What's this?)

I bought the Polk db651s speakers to replace the stock speakers and to see if they would improve the music from the stock radio/cd player in my 2010 Accord. The speaker upgrade was fine but not enough volume. I bought the Alpine power pack and WOW!!!, at least a 100% increase in volume, and the clarity/quality of the music was significantly better. I went to a professional installer and at first he was skeptical because of the size of the Alpine 445U Power pack, but after he had it playing all he could say was WOW!!!

Pros: Size (easily hidden) Lots of power, WOW factor.

Cons: Had to go to a pro for a seamless install.

Nice little factory upgrade

Jeremy from Indiana on 5/15/2013

Crutchfield Customer Review (What's this?)

This little Alpine amp is a great upgrade to my factory 2013 Jeep Wrangler Unlimited factory radio (U130). It at least doubles the power to be plenty loud to damage your hearing, you can pretty readily find somewhere behind the dash to stick it, and it just splices right in to the factory radio wires including no need to run power wires from the battery (which I did anyway for a Kenwood KSC-11 powered sub). I didn't have preamp outputs on the factory radio, so all I had to do was cut off the RCA connectors on the Alpine and splice line level wires right in to it. I do recommend adding extra wire to the inputs side for placement flexibility if using line level inputs (speaker wire works fine); I don't fault Alpine for this because preamp inputs would have used a longer RCA patch cable. I haven't heard any noise either adn that is just using the factory radio harness inputs. Some nice aftermarket speakers, like the Kicker 6.5" CS component and 2 way sets like I added go well with this and their 100 watt RMS power handling mean zero distortion and no way I can blow the speakers.

Pros: size, relatively easy wiring for an amp

Cons: Crutchfield didn't have a current wiring diagram but sent what they had & I figured it out by looking at the wires & cutting one set at a time, "only" 45 watts per channel RMS, adding a full amplifier with 60 or 100 W RMS like one of the new small digital ones wouldn't be much more complicated and pricing would be similar

Alpine KTP-445U Power Pack

Mike from Western PA on 5/12/2013

Crutchfield Customer Review (What's this?)

I didn't realize what I was missing! I needed to replace the factory amp in my 2002 Chevy Avalanche because it literally burned up leaving me with sound only on the left side. The install was not easy because wiring different colors from the amp to the vehicle harness could get tedious. The biggest problem was that the amp control wire from the Sony head unit and the wire from the amp are blue and white; in this Chevy, though it was pink. If I would have read a little more in the Avalanche Service Manual and the Crutchfield online sheet, I could have recognized it. But it went in and immediately I noticed the difference. It might not be a butt kicker, but it is a huge improvement over the factory amp that overall I was satisfied with. With new Kickers in the rear and recent Kenwood compnents up front, it's now a beautiful thing in my old Av!

Pros: Small size made it easy to mount where the old amp was, and I even temporarily had it in the glove box. Easy connection to head unit. Plenty of wire length to tie output to the factory harness. GREAT sound.

Cons: Terrible installation chart and directions- not logical and hard to read partly because they put 3 languages onto each line of the diagram. Also "instructions" for dip switches and remote wire were useless. Short RCA leads to head unit.

Cost effective upgrade

angryshuna from Boston, MA on 5/7/2013

Crutchfield Customer Review (What's this?)

I have 2012 Impreza. Love the car, like the features of the head unit, bluetooth, aux cable, usb input, etc. Hate the sound. From reviews, I discovered that the speakers were fine but that the head unit put out a measly 10w per channel. I looked into and bought this product thinking that I could improve the sound without rewiring anything or gutting the head unit. Sure enough, paired with a breakout harness (mfr in, mfr out, all splicing between connectors), I was able to get this up and running in about an hour. Huge improvement!!

Pros: Great sound for little work and little $.

Cons: Need room in dash for extra box and wiring behind head unit

Great amp

gasman from michigan on 5/6/2013

Crutchfield Customer Review (What's this?)

Who says good things don't come in small packages? This one does. I was looking for something to add a little boost to my RV sound system. The magnadyne head unit just didn't have enough oomph. I started out by changing the speakers to Polks, but not enough power to drive them sufficiently with the receiver alone. I was on the fence about an amp so small, but didn't want the hassle of wiring a big amp if I didn't need to. With Crutchfield's 60 day try it or send it back if not happy policy, I figured I had nothing to lose. The other reviews of this amp were also good. Well, I'm glad I did. The system came alive. The only issue that I had was that there was initially some interference/ noise present. This was resolved by turning the gain down on the amp. I mounted the amp behind my seat, so I had to make a longer harness to reach the radio. The whole process was straight forward and the directions were accurate. I highly recommend this amp.

Pros: Great price. Great power and clarity for a small form factor amp. Easy set up. Crutchfield service...

Cons: none

Perfect fit

Harley from USA on 4/30/2013

Crutchfield Customer Review (What's this?)

This unit fit in the tight space I had on my motorcycle. It was a perfect compliment to the Alpine IDAx200 head unit. I have the Polk Audio MM series speakers and the additional power gives them great sound at high volume.

Pros: Great price, small size, RCA connections

Cons: It took a little time to figure out wireing but not a big deal.

Powerful, Small Amp

Aaron from Indianapolis, IN on 4/28/2013

Crutchfield Customer Review (What's this?)

This little amp is awesome. I have a 2004 Honda CR-V and recently replaced the factory speakers with a couple pair of 6.5" Polk Audio db651s. I didn't want to replace the head unit but wanted more power coming through my speakers. One of the Crutchfield reps helped me find this amp which was a huge sound upgrade. This thing can really make the speakers scream. This was my fist amp install so I wanted a relatively simple one. Through a lot of research, YouTube videos, and a little Crutchfield technical support I had this guy installed an sounding great. Can't recommend Crutchfield enough. Great products, outstanding customer service, and an incredible company.

Pros: Small Size. Lots of Power. Able to mount behind the dash.

Cons: Most of the wiring is too short unless mounting directly behind the head unit, but nothing some additional speaker wire can't fix. Instructions could have been designed better.

Overall pretty good, but.....

Patrick from Chester, VA on 4/28/2013

Crutchfield Customer Review (What's this?)

I bought this little amp as a quick add-on and wanted some extra power, also to bypass the built in crappy IC chip amplifier that is found in just about ALL car receivers. What drew me was the bridging capability of "90 X 2" claim, it's small size, and can piggy back it's power from the car radio circuit. I use this in an older hatchback style Honda Civic with just the 2 door speakers. Plugged into a Pioneer DEH-9500BHS, with some Pioneer 6.75" D170's, it was a significant improvement over the radio's built in amp. I did notice that this amplifier can "clip" easily if overdriven, which can potentially damage your speakers. I called Crutchfield and they said maybe the gain was set too high. I don't think it's the amp, just what it is. Not sure if it will clip in 4 channel mode, but I'm only driving the 2 Pioneer door speakers-which are super efficient. I played with the gains taking note not to set them above the halfway mark. I turned them down a bit and was about to get a little more out of the amp, but it will still clip if the volume/bass is set too high. Overall not bad for the money, but don't expect a miracle or to blow the doors off. Kind of reminds me of the "add-on power boosters" sold at cheaper dept stores from the late 70's & mid 80's. If you're looking for more power in a small size, they're other amps out there for about the same price, maybe a little more. The only downside is you'll have to buy an amp wiring kit and long RCA patch cords.

Pros: Size, Price, Sound improvement

Cons: Can clip easily, touchy gain controls, short RCA plugs

Just Right

Steven from Charleston, WV on 4/27/2013

Crutchfield Customer Review (What's this?)

Installed in a 97 Jeep Wrangler. Install along with Kenwood KMM-100U reciever and Polk Audio speakers. Being in a Jeep (i.e. tent on wheels) I wanted to get something to push a little more power to get more volume and to also get a little more clarity. Based on Crutchfield reps recommendation this was perfect. It is small and fits behind the receiver and is out of sight. (invest in zip ties) Wiring it was a bit tricky but made sense once I did it wrong the first time. Wiring still went fast. You basically end up wiring all of you main wires was from the input side and you speakers you wire in from the output side and you are good to go. This unit does as advertised. A lot more clarity and detail in the sound. More power what was 35 on the volume scale of my reciever is now a 25 -26. No distortion at the higher volumes either.

Pros: More clarity and detail Great recommendation for something I would never have found on my own Out of the way

Cons: For non Alpine units you have to think through the wiring (you may need extra speaker wire as well as the output side is a bit short)

"Power Pack" says it ALL! Class D amp = A+

Toddman from N.Tx on 4/27/2013

Crutchfield Customer Review (What's this?)

I have been looking for a small amp to power my Infinity front & rear door speakers in my '00 Sierra. I upgraded the head unit & the speakers awhile back & didn't feel the need to get an amp at the time. I didn't know what I was missing until I hooked this baby up. My sound system came alive with the sound I new it could produce. It wires right into the factory harness adapter that was used when adding the Pioneer head unit. Everything is color coded for easy installation. You can use preamp input or line level inputs depending on your head unit. ** Don't forget to get some Posi-ProductsT Car Stereo Connectors they'll make the job A LOT easier. ** It has all the controls you'll need like crossover points & gain controls in a small compact case. It will really surprise you for it's size & it's a CLASS D amplifier! To round out my system I added the Sound Ordnance B-8PTD under the backseat to fill in the bass.

Pros: Class D amp Compact size, compact price Easy to install (wires inline with radio) Alpine quality sound 4 channel or 2 channel application

Cons: Wire leads a little short


Anonymous from clinton md on 4/8/2013

I was very hesitant but im glad i chose this amp. It brought my speakers to life with no distortion at all alpine 6/9s next thanks for your advice crutchfield all the advisors are great

Pros: Fair price


04 Wrangler Sport Stock HU

wedu22 from Groton, CT on 4/8/2013

Great item and was exactly what I needed to for my Stock Radio in my Wrangler. Small & easily concealed from prying eyes. Really surprised at the boost it provided to my OEM HU.

Pros: Small, powerful & great sound!

Cons: Original concept was for plug & play into Alpine stereo's easy to connect. The 445U (U for Universal) concept would have been better designed with longer RCA connections.

Alpine KTP-445U Power Pack

Anthony from Houston, Texas on 3/9/2013

This little thing blew me away with the power it has. I have it running a set of Boston SR-60 components in the front and a pair of Alpine SPR-69 in the back of my 2010 Nissan Altima coupe and this amp gave an immediate sonic improvement. Detailed mids and perfectly bright highs along with adequate bass (for what my current speakers are). Once again, Alpine makes another landmark item for car audio enthusiasts.

Pros: Great concept for my needed application, very high quality

Cons: Wish Alpine would make a 100 watt version, short RCA cables, tricky crossover location if its mounted to a solid surface

Good product.

9859limited from Massachusetts on 2/3/2013

I had my doubts this amp would make any difference but let me tell you it has cleaned up the sound of my system very nicely.

Pros: small, easy to hide, inexpensive, and pretty simple to install.

Cons: non really just wish alpine could make one with more power output.

sound quality

Anonymous from Washuington state on 1/14/2013

Crutchfield Customer Review (What's this?)

I messed up by ordering the univeral unit instead of the plug and play unit, my fault. Crutchfield offered to exchange it but I proceeded with what I had. It works very well and I am pleased with the high power output. However when I increase the volume to a level I would not normlly use, it cuts out momentarily. I set the dip switch as recommended but something is wrong here. Overall a huge upgrade. I combined an Alpine CDE-134HD with this for use in a class C motorhome. I did a speaker upgrade last year.



2009 Hyundai Santa Fe (Stock Radio)

mobrien1968 from Long Island, NY on 1/3/2013

Crutchfield Customer Review (What's this?)

Purchased this amp for my 09 Hyundai Santa Fe w/ stock (Non Infinity) system. In order to install this without cutting any of the factory wiring (and to ease the installation), I purchased the Parrot bluetooth harness ($30, Crutchfield). Without the harness this amp would have been a whole day project. In agreement with the other reviewers, the wiring harnesses included with the amp are WAY too short. But all said and done, it is a huge improvement. The separate front/rear crossovers help in tuning it, as the front speakers are different from the rears (component vs full range). I was able to cancel out the low freq. bass from the rears, which could not handle it very well. I would have rated it 5 stars if it wasn't for the short wiring harnesses included with the amp.

Pros: Small size, can mount almost anywhere, does not require direct power from the battery (low current draw)

Cons: Included wiring harnesses way too short, unless you can mount the amp directly above or below the radio. Instructions somewhat hard to read (small print).

2005 Camry LE (JBL)

Maxberry from Cincinnati, Oh on 12/21/2012

This Alpine Power Pack works great on my 2005 Camry (JBL) system. I upgraded my factory JBL receiver to the JVC KWAV60 and put this Alpine on and new speakers. Whole new ball game. This thing is great. Make my speakers sound so much better. If you have that factory JBL Amp in your car you must get the "Metra 70-1761 receiver wire harness For select 1987-up vehicles" also sold by Crutchfield. This Metra 70-1761 harness will bypass the old JBL factory Amp so you can put the Alpine Amp on - connect these (comes as two harnesses) to the car harnesses just below the receiver.. So make sure you don't get the "Metra 70-8113 Toyota Receiver Wiring Harness For select 2000-07 vehicles with factory amplifier" because this harness will integrate the factory JBL Amp than you can't use another amp. I had to find out the hard way. Hope I helped other Camry owners..

Pros: Sounds great and it's almost plug and play.

Cons: None

Great product!

Matt from Santa Fe nm on 12/8/2012

Crutchfield Customer Review (What's this?)

Great product and sounds great!

Pros: Easy to install and sounds great!

Cons: The wires on the unit are short, which limits where you can mount it.

2012 Ford F-150 XLT with Sync

Joseph from South Carolina on 12/5/2012

Crutchfield Customer Review (What's this?)

I was able to make this a plug and play amp by following online instructions. Just Google it. By doing that I was able to drive a pair of Infinity speakers giving the truck a much clearer sound. The install is easy and the sound is great. I recommend highly.

Pros: Ease of installation. able to use a Metra Bluetooth harness to make it plug and play.

Cons: Had to take dash apart several times to adjust sound and move wires. The sound to the front right kept cutting in and out.

Does the job

Midniteradio from gainesville ga. on 11/21/2012

Crutchfield Customer Review (What's this?)

I Installed this amp in a second car I use to run about town in a week ago. Paul at Crutchfield helped me complete the install when the instructions got vague near the end, thanks Paul. The entire install was an entry level job, entry level Alpine CDE-121 head unit, 6x9 Alpine E-series in back, and cheapo Kicker 11DS60 6.5" 2-way Car Speakers in front and this little amp makes them pack all the wallop they can. After playing with the amp settings I am happy with the sound and considering the entire car stereo install was about $350 I am pleased to have this unit. I usually run winamp through my phone for music and the 10-band eq in winamp makes this entry-level system sing. I recomend this power pack.

Pros: Clean power, size, options.

Cons: Instructuons are lacking, big time.

great little amp

wayne g from slidell,la on 11/15/2012

Crutchfield Customer Review (What's this?)

got this to try with a jvc head unit and it rocks.if your thinking about it, stop and just BUY ! you won't be sorry. althou it won't blow the windows out,it will add clairty with the right amount of kick

Pros: price,size,ease of install

Cons: none

awesome little amp

Mark in ohio from Findlay, OH on 10/20/2012

Crutchfield Customer Review (What's this?)

Using with polk db's 6.5 inch x 4. Sounds great and makes factory deck 10x's louder in my Kia Forte. does fit behind dash too.

Pros: Sound. size. quality.

Cons: None

A BIG surprise from small product.

Darryl B from Lansdale Pa on 10/17/2012

Crutchfield Customer Review (What's this?)

Bought this amp to boost the signal form my JVC HU. What a difference! Full Range mode really makes the speakers scream while being clear. The physical size of the amp made it a breeze to tuck away. If you buy this amp. you won't be disappointed.

Pros: small compact design. Long wires on the harnes makes it easier to find the right location to mount,

Cons: Non yet...

best ever

Anonymous from fargo nd on 10/10/2012

Purchased to run to run a set of alpine type S components in the front and a set of alpine type S 6 and a half in the back sounds amazing

Pros: Easy to hide behind dash great price for the amount of power

Cons: Haven't found 1 yet

Alpine KTP-445U Power Pack

John M from Vernon, NJ on 9/25/2012

Crutchfield Customer Review (What's this?)


Pros: small size fit behind dash, high and low onputs, low and high filters, clean sound, price

Cons: short wires, had to add more wire to reach head unit

Very Nice

Mr. Mike from Adamsville GA on 9/22/2012

Crutchfield Customer Review (What's this?)

This little thing gets the party started. I use to have to turn my radio up to around 15 to drown out the road noise when the windows were down, and now the same level is achieved at somewhere around 6. It is small enough to be hidden easily, but it was not small enough to fit behind my head unit as the add suggests. Maybe if I did not have a double-din sized head unit, then it may fit. It features a high pass filter for the front and rear channels, so you can keep those lows away from your delicate speakers. The best thing is that you don't have to run an amp wire through your firewall, because it can work off of the wires that use you use to connect your head unit. I would recommend this to anyone.

Pros: Small, Powerful, Hi pass filter

Cons: Not quite small enough to fit behind the head unit if you have a double-din unit.


LARRY M. from PASCO WASHINGTON on 9/12/2012

Crutchfield Customer Review (What's this?)

If u have an under $300 stereo system then this product is well worth the purchase. Poor quality before purchase and what a difference after installation!!!!!!! Enjoy the results.....

Pros: Easy install with no special wiring or equipment. Excellent quality for the price!!!!!!

Cons: Not marked as to the stereo wiring in and speaker wiring out.

ktp 445u

eddie h from chicago il on 9/9/2012

great upgrade to any system stock or much easier to install than any other amp instructions show you different options of installation which is great.this amp really kicks hard just make sure you adjust the amp as per instructions.i would not recommend this amp if you are still running stock speakers because it wont really sound any cleaner just louder so aftermarket is the way to go on the speakers.

Pros: easy install clean sound even at high volumes impact amp will fit anywhere

Cons: wiring harness a little short

Power Box Amp

Marcos from El Paso on 9/4/2012

Crutchfield Customer Review (What's this?)

Excellent addition to my HU, made my car speakers come to life, very compact and easy to hide behind my HU in the dash area. (2012 Honda Ridgeline)

Pros: Compact and enough power, no running wires.

Cons: If you want to be heard coming down the street, get a more powerful amp.

Hard to hook up

Anonymous from Hawaii on 8/31/2012

Crutchfield Customer Review (What's this?)

Had to return the amp because I was told it was plug and play...far from it. Had to actually cut the RCA jacks to hard wire...still did not work...finally after 4 hrs and 3 calls to tech support at Crutcfield, eith no real help..sent it back. Really wanted the extra power, but way too much involved to hook up to my new Alpine deck, especially this day in age.



Just perfect w/137bt

Steve Mac from Missouri on 8/30/2012

Crutchfield Customer Review (What's this?)

Works great w/137bt!

Pros: Fits rite below the head unit in a 05 Liberty!

Cons: None so far!

Good amp, just not for me...

Chris from Lexington, KY on 8/24/2012

Crutchfield Customer Review (What's this?)

Giving it 4 stars because it's well built, puts out what I thought was good sound, the size is great, EASY installation with power/ground wires going to car harness, and overall quality is excellent. However, I have an 07 Corolla with a Dual head unit and Infinity speakers front and rear. With the proper settings on the Dual, believe it or not, I really couldn't hear any noticeable difference in the quality of sound. Based on the reviews, I was expecting cleaner and greater sound, but just didn't happen. I tested my system with the amp, then immediately after without the amp, and immediately decided it wasn't worth keeping, at least not in my car. If and when I get another head unit, or maybe another car, I will definitely reconsider this amp. One thing I noticed was how warm the amp got after a while. I would recommend this amp for anyone looking for good quality, and if your system is in need of decent power.

Pros: Size, easy install, good quality build.

Cons: Got fairly warm.

Alpine amp

BillyD from Myrtle Beach, SC on 8/21/2012

Crutchfield Customer Review (What's this?)

I really like the size of this amp and the power it puts out, Especially how it connects to the harness power wire. NO running wires through the firewall to the engine battery. There are many ways to install (RCA, wire harness) and the settings are convenient along with the gain knobs. I would purchase this product again.

Pros: Cool design, very small for 45watts of RMS! Adjustments easily modified.

Cons: Very short harness doesn't allow you to give much distance from the amp to the head unit. Currently have a lot of static in my speakers, Assume its due to the amp being so close to the head unit and the ground wires all sharing the same terminal.

alpine 445 power pack

John R from Marshall,N.C. on 8/18/2012

Crutchfield Customer Review (What's this?)

Could not be happier with this purchase! Easy to install and will fit just about anywhere..Plenty of power for me!



Good amp for price

Chaz from Cleveland on 8/17/2012

Crutchfield Customer Review (What's this?)

I had a very good recommendation from associates for this equipment. Gave me all the info I needed to install and good product for the price

Pros: Easy to install even with OEM equipment

Cons: None

Alpine is Fine

David R from Lewisburg, WV on 8/14/2012

Crutchfield Customer Review (What's this?)

This little amp is just what the Doctor ordered, small but yet powerful & very clean sound. I paired it with a new Alpine CDE-122 head unit with some new JBL 5 1/4" coaxials, what a difference. I already had a amp/sub in the trunk so this update really blended everything great!

Pros: Small, simple hookup, provides efficient good clean power to all 4 speakers. Would definatey recommend & would purchase it again.

Cons: None

Easy To Install

42 years old from Indiana on 8/4/2012

I was a little hesitant to get this amp from reading the reviews on installing this amp, but I decieded to get it anyway and see for myself. My skill level is I have installed 5 car stereos in 25 years and this was my first amp I installed. So I get the amp open it up look at the directions then look at the wire harness that comes with the amp. Ok looks pretty easy go out take out the stereo and 20 minutes after I pull the stereo out I have it wired and working. Nothing to it. Directions were easy to follow. The hardest part was trying to find a place to put it with the short wires. So I went out and bought some wire, spliced it in, and GOOD TO GO. 4 stars four the wires being to short.

Pros: Lots of sound, easy install

Cons: Wires on the HU side are around 6 inches long

Great amp for small spaces.

JAKSON from Marlton, NJ on 8/1/2012

Crutchfield Customer Review (What's this?)

I recently purchased a mint condition 2001 Jeep Wrangler Sport LANDRUNNER EDITION. As many jeep owners know we are LIMITED on space to put any accessories anywhere in a Jeep. This small but powerful amp is weel worth the price. I now can here my after market stereo with the doors off and the top down cruising down the PA TURNPIKE at a good speed. I would have given the amp 5 stars if the wires on the input side were longer. I don't know what Alpine was thinking because in the direction they state do not mount amp close to the head unit. Well easier said than done. Other than that I Love this product and a couple of my friends are in the process of buying the same amp.

Pros: Compact size, mega power. Perfect value.


Exceeded Expectations

Curt D from Chaska, MN on 7/31/2012

I bought this amp as an upgrade from an OLD Alpine amp that was rated for 20W/ch. I'm running it in two channel/bridged mode driving my front speakers. I have the power lead hooked into the distrubution block with my other amp and 8AWG wire from the battery. I was initially sceptical of the 90W rating for such a small package. Boy, was I pleasantly surprised the first time I fired it up! It is ROCKIN my Boston coaxials plus seperate tweeter set. There is a great improvement in bass and accuracy. String instruments actually sound like string instruments again and I'm getting decent bass in the front of the car. Now I know my speakers are performing to their full potential. I have to disagree with some other reviewers about the instructions, I thought they were very complete and easy to understand. I do have a very low level alternator whine like others experienced. I have not tried the ground isolators yet. In two channel mode this amplifier is for real.

Pros: Really has the power to back up the specs. Clean, pleasant signature Alpine sound. Well worth the price.

Cons: Suseptable to picking up noise. Filter module on the power lead is a little cumbersome if you want to pull the lead through a small space.

Not as easy to install as the old model

Stonefish from NH on 7/20/2012

Crutchfield Customer Review (What's this?)

When I got this I was expecting the old "plug and play" model, so I was a little surprised to find that it wasn't going to be that easy. Installation was a bit of a pain, the wires on the side that inputs form the head unit aren't even CLOSE to long enough. I ended up cutting off all the plugs and extending the wires about a foot and a half. Besides the install being a pain though, it's a great product. Good amp at a low price, sounds great. Going to have to replace those stock rear speakers soon, they're struggling. Took a star off for the short wires, they weren't even close to long enough. the pre-amp plugs were about 4-5 inches long

Pros: - Small size - Low price - Great sound

Cons: - Install was a bit of a challenge

alpine ktp 4445u power pack

Stacy from chesapeake virginia on 7/11/2012

Crutchfield Customer Review (What's this?)

The power pack is a good product and has the power the only thing is the rca cables need to be longer than a ft. I will have to buy 4 more to make it work. They were not long enough 40 more $

Pros: Lots of power

Cons: Cables not long enough

Awesome for price

ToyzFor bigboyz from Howard, KS on 7/9/2012

Crutchfield Customer Review (What's this?)

Decent amp for money. Great amp for beginners to install. Pair this amp with a pacific accessory corporation oem 1 in a Tahoe and install takes 15 minutes. Great for fronts and rear speakers but does provide ample crossover points for fine tuning. Allows too much bass that distorts mid bass drivers, and too much top end highs,over 8k kHz.

Pros: Cost, efficiency, installation

Cons: Crossover points

compact, powerful amp

todd t from chillicothe, oh on 7/8/2012

Crutchfield Customer Review (What's this?)

Excellent amp, compact, doesnt get to hot, i was able to stash it under my dash without worrying it would get to hot. if adjusted proberly you will have able power for most peoples needs. good, clean power.

Pros: small, powerful, low heat

Cons: once i stashed it under the dash i wasnt able to adjust the gain on the make sure you have it adjusted before you stash it in close quarters......or leave it looks good enough to display.

Great little amp

MattM from Boston, MA on 7/8/2012

Crutchfield Customer Review (What's this?)

This is a great amp. I have this installed with an Alpine CDE-137BT and they make a great combo. I used the RCA pre-outs from the deck to the amp so I did not run into any short cable problems like the other reviewers here. It fit just under my receiver in my Saab -2x (exactly the same as a Subaru WRX 2002-07). This makes the factory speakers sound far better than the factory HU. I will probably still buy replacement speakers, but I will say that this was a huge improvement to the factory speakers, depending on your preference you may not even bother with a speaker upgrade. The unit is a little wider than a standard size HU so it was a little harder to fit under the HU but it should be doable in most cars. The supplied mounting hardware is minimal... I went out and bought some velcro to secure it behind the dash better. If you do have to cut the pre-outs off, there is barely enough cable to work with, Alpine needs to add another 6 inches to the RCA cables. I think that if you are serious sound (and volume) nut then a full four or five channel amp is the way to go, but for the 98% percent of us who want solid sound but still want to keep our ear drums this is a FANTASTIC unit, 45 watts RMS x 4 is more than adequate. Four stars (instead of five) mainly due to pre-outs and crap instructions. I'll update when I install some aftermarket speakers as well.

Pros: Much easier to install than running traditional amps because of no need to run wire to battery. Surprisingly good sound for such a small package. Brings new life to factory speakers. Size.

Cons: RCA pre-outs too short. Width is wider (slightly) than the standard DIN width. Instructions do kinda suck.

As Advertised

SG from Greater Boston, MA on 7/6/2012

Crutchfield Customer Review (What's this?)

This is a simple, small amp, fantastic for driving speaker-only setups. It is a definite improvement over head unit power alone. I paired this amp with an Alpine CDE-137BT. Far more headroom, and am hearing parts of songs I was not able to pick up with before installing my new system. Very happy. Only downside is that I had a tough time finding a good spot to hide the amp, and found the powdercoat finish fairly easy to chip. I wound up using velcro to fix the amp to a vertical dash support behind the glovebox (in case I want to play with the high pass filter options, I wanted it to be removable.) Seems to be holding OK so far. I also had to purchase longer RCA cables, as the included RCA extensions are not long enough to mount the amp anywhere but behind the head unit (which was not large enough to fit the amp in my vehicle.) If using the speaker-level inputs, this problem goes away.

Pros: Headroom, clarity, size

Cons: Mechanical quality of powdercoat finish (chips easily), short RCA exentions

Just what I needed...

PVP from Atlanta, GA on 7/6/2012

I wanted to add a little more punch to my wife's Corolla 2007, but had to keep the factory radio. I installed this "mini-amp", replaced the factory speakers, and added a pair of tweeters. Even better, I found the factory tweeter door mounts/moldings and the corresponding male and female harness connectors so no cut factory wires. Also installed an iSimple PXDP that charges and controls an iPod/iPhone4.

Pros: Sounds great. Probably equal or better than optional JBL 6-speaker system Toyota offered, but at a fraction of the cost. Installed fairly straight forward. Needed to add more wire to speaker level portion of harness so that I could mount KTP-445U to the far right of dash just above glove box.

Cons: Alpine instructions almost useless; the sole reason why rating is 4 star and NOT 5.

i like......

andy b from dallas, tx on 7/5/2012

Crutchfield Customer Review (What's this?)

2000 silverado extra cab ---- gives a good boost to your speakers, Im using this with a Kenwood that seemed like it lacked power and after installing it in my truck the difference was very noticable - more bass, more sound all around. It was quick and easy to instal, the instructions are a little weak and slightly longer rca cables would be helpful - maybe another 6 inches or so but thats easy to fix. I installed it using the pre-outs spliced directly into the radio power (like it says to) and have no issues with it at all, I am still fine tuning the gain settings but I am very happy with it- makes a sub. a little less necessary (but Im doing it anyway next day off). for anyone whos interested, infinity 6 1/2 components and pioneer 4x6's (thanks chevy for the small speaker size) in back. Only reasons for 4 stars: poor instructions, short cables and I do wish it was a lttle more 'full' in the low volume area but that could be my kenwood or the speakers. But a definate improvement and Im glad I have it.

Pros: easy upgrade for those looking for a litle more power without the trouble of running amp power and wires- easy to instal, small and it does make a big difference to the sound- worth it.

Cons: marginal (poor) instructions and since this is geared to the less serious consumer (the ones like me who just want better sound), clear instructions on setting gains and other settings would be helpful as well as longer rca cords - I know we can buy them but just a little longer would be nice.

Alpine KTP-445U Power Pack

Anonymous from Copiague Ny on 7/5/2012

Crutchfield Customer Review (What's this?)

Good product worth the money

Pros: Small. Versital

Cons: Instructions


Dennis H from Ocala, Florida on 7/1/2012

Crutchfield Customer Review (What's this?)

easy install, clean power

Pros: had previosly installed Infinty speakers in my 03 Silverado, amp really brought them to life

Cons: none

Great Sound - small package

TomW from Springfield, IL on 6/25/2012

Crutchfield Customer Review (What's this?)

Installed this in our boat and bridged to feed 2 6x9's. Made a huge difference and brings a new level of clarity and depth to the music. Great performance in a small package. Relatively easy to install - instructions are a little lacking, but the crutchfield advisors can fill in the gaps if need be. The only negative reviews that I've seen out there seem to be from people expecting more power than what ANY 45x4 or 90x2 amp can provide. I'd choose this over comparable output standard amp every time. Specials thanks to Advisor Norm for talking me through my setup and steering me this direction!

Pros: Sound, ease of installation, compact size.

Cons: none so far.

Nice & Easy !!!

Mike A. from Independence, LA on 6/20/2012

Crutchfield Customer Review (What's this?)

Fairly Easy to incorporate in my new system ( WITH help from the Crutchfield Guys over the phone !!! THANX !!! ) No need for battery power wire to be run through firewall ( Been there/ Done that - - Never Again! ) Makes my 6 year old 3-Way speakers in my '03 Tundra sound GREAT... Should have gotten an Amp when I bought my previous reciever that recently gave up the ghost but didn't want the "Hassel" of wiring and placing an Amp in a Pickup... This AMP simply goes where the old Toyota amp was and no "special wiring" to battery required... It comes with "items" to reduce ignition noise if present and a grounding wire attachment - I tried it without either and it is working Perfectly...

Pros: Relatively Small - Easy to incorporate - No special Power attachment needed - Clean / Clear Sound...

Cons: NONE... Highly recommend...

Good amp for the price

Erik from Cleveland, Ohio on 6/18/2012

Crutchfield Customer Review (What's this?)

Very easy to install if you have ever installed a head unit or amp before, I imagine the instructions would take a little longer for someone who hasn't. I had a Alpine head unit already in and used to turn up the volume to around 15-20 for everyday driving, now I only turn it up to 5-10 and it sounds much louder and clearer. This may have to do with the fact I installed a sub and mono amp so the speakers don't have to worry about producing the low frequencies anymore. I would recommend this for anyone looking for a volume increase and something that doesn't cost a lot for better sound.

Pros: easy to install, definitaly a sound improvement

Cons: the length of the cable on one side of the unit is way too short, they give you like 3 feet on one side and only like 5 inches on the other....

More power, less hassle

2006dodgepowerwagon from AK on 6/15/2012

Crutchfield Customer Review (What's this?)

As advertised.

Pros: More power, less hassle, easy to hide


Awesome little power hose

Stefan from Bismarck,at. on 6/13/2012

Great power easy to hide big increase in volume would have gave it five stars but the directions are useless .easy adjustments great sound just work on the instructions alpine!

Pros: Power,sound,compact

Cons: Directions stink


Yankee from Greenville S.C. on 6/7/2012

Crutchfield Customer Review (What's this?)

Alpine made an awesome product just what head unit needed sounds great and easy to install.

Pros: Small and powerful. Sounds so clean.

Cons: None

Alpine KTP-445U Power Pack

Anonymous from Lawrence, KS on 5/31/2012

Crutchfield Customer Review (What's this?)

I bought this amp because it is plug-and-play and requires no extra wiring. Once you figure out how to hook it up, it is fantastic. However, the included instructions are difficult to follow and when I called Crutchfield support (as of 5/14/2012) they had NO IDEA how to install it--they said they had not been given any information yet. Once Crutchfield supplies coherent instructions I would rate this a 5 out of 5. Fits perfectly under my receiver in a rsx.

Pros: Size

Cons: Instructions are not helpful

Great Amp

Anonymous from new york city on 5/26/2012

Crutchfield Customer Review (What's this?)

This is the most amazing amp for one the size fits right into dash board and runs off the electrical wires for the head need for any amplifier installation kits.......i am powering 2 sets of polk audio DXI6500s front and back speakers i can crank them all the way up and no distortion at all pleanty of power! it is a musty have for someone thats wants to improve there audio system with out installing a ton of amps.......this was the first unit my installers ever installed they couldn't believe the clean power this thing dished out and install was a breez!

Pros: small,ez install for professional installer

Cons: none so far.................


David from San Antonio, Tx on 5/24/2012

Crutchfield Customer Review (What's this?)

Perfect size for my 2004 Wrangler. Directions a little hard to follow, but once I got it figured out, it was easy. Perfect fit in the dash behind stock AM/FM/CD. Appreciate the adjustable gain for both front and back..turned front up a little more to power the dash speakers which angle slightly downward. Crisp highs. I'll add a sub later for the missing low end, but very pleased.



Very pleased

Texgator from Dallas, TX on 5/12/2012

Plug-n-played with new Alpine deck. Drives Sound Ordinance speakers in 2012 Xterra to impressive, distortion free levels.

Pros: Size, sound, price and installation ease

Cons: None yet

A lot of amp for the money...and size

Perry from Kathleen, GA on 5/1/2012

I wanted an amp for '04 Jeep Wrangler, but did not want something so massive as to take up what precious little space I have now. This amp fits the bill perfectly. The hardest part of the install was interpreting the directions. The blue wire is neccesary to turn the unit on! I did not get that from the directions. Once I was able to understand the gist of it I tackled the installation. I installed mine behind the Kenwood head unit. I like that it tucks away out of sight and I can get to the gain adjustments while it is in the dash. I put my MP3 player connected and paused and with the gain turned all the way down, I turned the volume all the way up. If your hearing is good you can listen to the speakers as you turn the gain up. Once you hear the "hiss" from the amplifier STOP! Turn it back down and try to find that threshold of hiss! Repeat for the rear and you are done.

Pros: Compact size, good sound clarity

Cons: Directions....

Wow! Big sound from small package

JeepDude from Atlanta,GA on 4/30/2012

I added it to a entry level sony head unit in a 2001 Wrangler.Before installing the amp , I had already upgraded speakers to Boston Acoustics in the sound bar and Alpine's in the dash, all 5-1/4". Could not hear the radio over the tire and wind noise, especially when top and doors off. I installed this amp with hopes of getting a little more volume. It too me about 2 hours to install, could have done it in an hour if I hadn't lost a screw under the seats, and rewired the hack job from the previous radio installer. It should take you about an hour. I used high level speaker input to the alpine amp, the instructions have you cut the RCA plugs off, and use the wires,my complaint is it leaves you with about 5 inches of wire to work with ( - one rating star) ,making the amp hard to mount any distance from the head unit. I didn't want to cut into the jeeps wire harness further down the line, so I cut into at the head unit. I wish Alpine would have considered making these input wires about 12 inches, it would have helped out. Once installed and easily tucked into the dash I powered it up, WOW !!!!, this is a huge improvement. Took it for a test drive with no top or doors, sounded great ! I am really surprised that this amp brought out the sound quality like it did. I like the ability to adjust the gain on front and rear balancing out the sound. Instructions are ok, mounting hardware worked well for me, wire colors matched up making it easy to install for a DIY person. Great upgrade

Pros: Sound quality , size, price.

Cons: speaker level input wires a little too short for easy install . 12-14 inch input wires would be a great improvement. allowing placement further from head unit is a less dense area or the dash.


Hands-on research

Product Research


Overview: The Alpine KTP-445U Head Unit Power Pack is a power upgrade amplifier that allows you to add higher output and more dynamic response to your aftermarket or factory installed car stereo system (without factory amplifiers). The KTP-445U amplifies your aftermarket or factory head unit's power output, resulting in increased power over the original head unit's built-in amplifier. It's small and compact at only 7.875" (w) x 1.5" (h) x 2.5625" (d) and fits behind the head unit in the dash of most vehicles. The KTP-445U comes equipped with RCA and auto-sensing speaker level inputs.

  • If the fuse protecting the OEM radio is less than 15 Amps, you should run a separate +12V constant power wire from the battery to the higher-powered Alpine KTP-445U.
  • This Alpine high-powered amp won't work in systems where an outboard factory amplifier is still active. If used in vehicles with a factory amplifier, the factory amp will need to be completely bypassed (this may result in lost speaker channels, if factory amp has more than 4 channels).
  • The increase in power may result in a louder warning chime in certain vehicles.

45 Watt x 4 Channel Amplifier: The Alpine KTP-445U Head Unit Power Pack employs a 45 watt x 4 channel amplifier. The amplifier offers an unbelievably low noise floor, taking extra care to ensure a clean signal path, with no extraneous interference. The end result is a 1 Watt Signal-to-Noise Ratio of 82dB or better. Uniquely, the amplifier distortion actually decreases at higher frequencies, resulting in a clean and clear signal where your ear is most sensitive to distortion (< 0.03% THD+N @ 1W; 1% THD+N @ rated power).

CEA-2006 Compliant: The specifications given by Alpine for the built-in amplifier comply with the CEA-2006 mobile amplifier power testing and measurement standards from the CEA (Consumer Electronics Association). All manufacturers who comply with the standard can display the CEA-2006 logo on their product.

  • CEA-2006 Power Rating: 45 watts x 4 channels (at 4/2-ohms, 20-20kHz, 1% THD)
  • Bridged: 90 watts x 2 channels (4-ohm minimum impedance)
  • Max Power Output: 90 watts x 4 channels (Peak)

Controls: The Alpine KTP-445U Head Unit Power Pack provides independent controls for the Front & Rear inputs.

  • Front & Rear Gains: The Power Pack provides simple variable gain controls (speaker level: 0.5-10V, low-level: 0.2-4V) for flexibility and a wide variety of system applications.
  • Front & Rear HPF: High-Pass selectable switches for the amplifier's Front & Rear inputs allow frequency filtering for a wide variety of speakers. Choose "Full-Range" or a selectable range (60Hz, 80Hz, 120Hz) to fine-tune your crossover points (-12dB/oct.).
  • Configurable Inputs: On the bottom panel of the Power Pack there are selectable input options to accommodate Speaker-Level (0.5V-10V) or RCA (0.2V-4V) inputs.
  • 4Ch/2Ch Modes: Selectable 2-Channel & 4-Channel options give you the control to determine source inputs, and can eliminate the need for Y-adapters.

Low-Level & Speaker Level Inputs: The Alpine KTP-445U Head Unit Power Pack includes a 5.5" low-level/speaker-level input harness. The harness features a proprietary 10-pin connector on one end that plugs into the KTP-445U and two pair of stereo RCA inputs that connect to your source unit's front & rear RCA outputs using a pair of stereo RCA cables (sold separately). If your source unit is not equipped with RCA outputs and only features speaker-level outputs, then you can cut off the included low-level/speaker-level input harness' RCA connectors (or use the optional Speaker Wire to RCA Adapters) and connect the KTP-445U to your source unit's front & rear speaker outputs.

Note: You will need to connect the amplifier's remote turn-on lead wire (blue/white) to your source unit's remote turn-on lead when connecting the KTP-445U via Low-level (RCA). You do not need to connect the remote turn-on lead wire when connecting the amplifier via speaker-level input, because the speaker-level inputs are auto-sensing.

Power/Speaker Output Harness: The Alpine KTP-445U's power/speaker output harness consists of a 16-pin proprietary connector on one end that plugs into the KTP-445U, and bare wires on the other end to connect to power/ground and your car stereo speakers through your vehicle's factory or aftermarket head unit's wiring harness. (What looks like a fuse holder in-line with the amp's power wire is actually a noise filter.)

Note: The factory radio circuit needs to be a minimum of 15A. If it is not, a separate power and ground will need to be installed for the KTP-445U.

Mounting: The Alpine KTP-445U Head Unit Power Pack includes cable ties to attach the amplifier to your vehicle's frame or chassis. The KTP-445U also includes two mounting brackets and four hex-head screws to fasten the amplifier to a flat surface of your vehicle.

Our Product Research Team

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Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

Advice from Rusty at Crutchfield tech. [ Jonn  Oct 08, 2017 ]
need compact Amp for JVC headunit we bought. need a little extra kick/cleaner sound to speakers at hight volumes. when top is down and rolling down road wind noise downs out sound. [ STEVEN  Aug 23, 2017 ]
Great Product, well worth the time and effort, great customer service [ JOHN  Jul 26, 2017 ]
Car specific. [ Gregory  Jul 08, 2017 ]
Recommend by a crutchfield advisor because my front speakers only run at 30w RMS [ Jeremy  May 18, 2017 ]
Compact and good enough to power speakers [ K  May 17, 2017 ]
I needed a low wattage solution to give my stock head unit a boost. I trust Alpine to deliver a great product. [ Jeffrey  May 09, 2017 ]
Small compact size, reliability, and ample power for my application [ BRIAN S  Mar 31, 2017 ]
love alpine brand [ ARMANDO  Mar 27, 2017 ]
This is going on my motorcycle and I needed an amp with a small compact design with good power ratings. [ Geoffrey  Mar 21, 2017 ]
Got this to add some muscle to car midwoofers without the hassle of drilling through firewall and patching into battery, as will traditional amp. Not sure I ever wired this correctly; never sounded right. Good reviews so probably my error. [ JOSEPH  Mar 14, 2017 ]
Wanted something more powerful than the factory receiver provided. Also didn't want to get into the big hassle and expense of big amplifiers. [ james  Mar 02, 2017 ]
bad ass little amp tied the system together [ KIPPLIN R  Feb 16, 2017 ]
my stereo has no bass and not good in sound. I have little ones that loves music, but I don't want it to loud for them. so I cant hook up my subs. I wanted something smaller that would give me that itch im craving :) [ JOSHUA  Jan 15, 2017 ]
inexpensive way to power after market speakers without changing head unit [ T  Jan 15, 2017 ]
Gift for son [ James  Dec 17, 2016 ]
This is the 2nd one of these for a separate vehicle. Good clean power for a reasonable price. [ W  Dec 17, 2016 ]
I have used these in the past and are great for sound and ease of installation [ Tommy  Nov 15, 2016 ]
Got this for a painless audio improvement in my Nissan Frontier. Originally purchased a Punch amp but later discovered I'm no longer interested in messing around with an amp installation. Keeping it simple. [ Evans  Oct 22, 2016 ]
I compared power pack to amplifier of more watts and the results were very interesting, the power pack won hands down on .....clear sound with better highs and mids....there is no comparison when it comes to alpines sound quality . so the alpine power pack with easy wire hook up and placement area of convenience will shock you pun intended! [ SALVATORE  Oct 21, 2016 ]
smaller size [ Juan  Oct 04, 2016 ]
It seem to fit my needs when I did my research, and the advisor when I asked about easiest amp installs. Chance recomeded this amp. [ Scott  Oct 03, 2016 ]
awesome little amp! [ al  Sep 30, 2016 ]
Saw this in the May/June Newsletter. Called Crutchfield, spoke with Buck, and decided to order this to increase the sound quality in my 2010 Rav4 Buck's Bio: [ Kevin  Aug 28, 2016 ]
Have better performance and clarity to my car audio system in the simplest and cheapest way. Sound quality [ Gustavo  Aug 26, 2016 ]
suggested by advisor [ doug  Jul 08, 2016 ]
Ease of installation is primary reason I chose the Alpine Power Pack. Also based on advice from Crutchfield, should provide additional power to enhance the sound system [ ERIK  Jun 06, 2016 ]
Everyone's opinion on how it works with Factory stereo [ John  May 17, 2016 ]
Great replacement for factory amp in my 2002 WJ Jeep Grand Cherokee, fit in factory location, used all the factory wires (left front dash disconnected, full-range speakers in the front doors) [ Thomas  May 08, 2016 ]
Compatibility with Alpine receiver, small size, ease of installation. [ Albert  Apr 08, 2016 ]
I'm upgrading the front door speakers in my BRZ with Polk db Component 4 ohms and am using this amp to replace the factory amp that only runs the door speakers and only at 2 ohms. [ William  Mar 09, 2016 ]
its an alpine [ Robert  Mar 02, 2016 ]
Compact, better sound from my aftermarket HU [ Ronnie  Feb 10, 2016 ]
I was looking for a small amplifier to add some umph to my factory. I knew I didn't want a full system upgrade. After looking around, the reviews made this amplifier stand out. [ Marc  Feb 08, 2016 ]
Compact design, great reviews, gain control for each channel. [ Miguel  Jan 18, 2016 ]
Daisy found an amp that would fit my tight space in my 06 toyota tundra. Daisy's Bio: [ Martin  Jan 06, 2016 ]
This amp is reliable, easy to install, and hides away nicely in the dash. It is a great purchase. [ ERIC  Dec 21, 2015 ]
It's super small and doesn't need a whole lot of power. just hook it up to your head unit or amp's power circuit as long as it has a 15A or higher fuse! 4 channels, low power. Perfect for tweeter and tailgate speaker combo. I wouldn't use it on door speakers though. [ Kevin  Dec 16, 2015 ]

59 questions already asked

Like most amplifiers, the Alpine power pack is not vehicle-specific. It's dimensions are: 7-7/8"W x 1-1/2"H x 2-9/16"D For additional assistance and personalized recommendations, feel free to contact us directly by phone or through our online chat service: [ Ryan  Dec 18, 2017 ]  Staff
Installed on a 2006 Dodge Ram. Had issues with the sound, so I had to install a new amp and bypass the factory amp. [ J C  Dec 12, 2017 ]
Nope...1997 Jeep Cherokee Sport. It was a very tight fit and I am now having problems as the head unit will no longer play so I am going to have to take it apart and trouble shoot. [ Ryan  Dec 12, 2017 ]
I would tap in before the amp so that it reads the unmodified signal. [ Ryan  Aug 05, 2017 ]
I do not know what head unit you are running, but on mine I plugged my powered subwoofer into the subwoofer output on the head unit. If yours does not offer that out put, my guess, not an expert opinion, would that you would run it off before the amp making sure you have a crossover on the line before your subwoofer if it does not have an internal one. [ Michael  Aug 05, 2017 ]
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can check and see if there is anything we can do to help. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer, or try our online support center: Here are a couple numbers that may be helpful. Alpine Customer Support 800-257-4631 Pacific Coast Parts (Alpine Parts Dist) 800-421-5080 Hope this helps. [ Kenny  Jun 19, 2017 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer, or try our online support center: [ Krissy  May 15, 2017 ]  Staff
Technically, what you have is 2 channels if your components use a driver. The answer is it depends on the requirements of the speakers. Don't expect 320w 6x9's, or 300+w components (at 2 ohms) to not cause the amp to go into protection, especially when summertime comes. Maybe if you have it in the cab or floor area where air conditioning can get to it, it may not be as much of an issue. Chances are your speakers aren't that rating, but it may be better to either use higher ohm speakers or a different amp. [ David Norris  Feb 19, 2017 ]
For additional details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on how everything integrates and what you will need for an installation in your vehicle. [ Kenny  Dec 31, 2016 ]  Staff
Thanks for your question. For information on selecting the best amp for your factory system I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Kenny  Nov 23, 2016 ]  Staff
Thanks for your question. For information on selecting the best amp I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Kenny  Nov 16, 2016 ]  Staff
Really sorry can't help u ,a friend of mine installed it for me but it's great [ ALEX  Sep 19, 2016 ]
It has been a while but I think there is a manual dial on the right side that you can set with a small screwdriver. I mounted mine so I could open my glove box to access the dials. [ MARK R  Sep 18, 2016 ]
The amp in the HU is bypassed completely. You'd still only have 45 watts RMS X 4. This is simply just a small amp. [ Michael  Sep 14, 2016 ]
No. The output of the Alpine amp is 45 watts x 4 at Ohms RMS. The Alpine can receive inputs of either line level or speaker level (which would be your HU's 45 watts x 4), but the Alpine will only put out 45 watts x 4 RMS. If your aftermarket HU already puts out 45 watts to four channels you don't really need this amp. [ Aaron  Sep 14, 2016 ]
Tristin: You will just have the power of the final stage of your alpine amp but I would bet the alpine amp is much cleaner than the 45watts out of the head unit. Best thing to do is if your head unit has pre-amp outputs connect those to the alpine pre-amp inputs this will be the cleanest sound. Otherwise connect your head unit (speaker) outputs to alpine speaker inputs. The cleanest sound and the preferred way to connect is preamps out of head unit to preamp inputs to the alpine amp. Either way it will not be 90 watts. Hope this helped. Regards, Jackie L. [ JACKIE L  Sep 14, 2016 ]
Not sure how hot it gets, but mine sits tucked away in the dash, behind the head unit where it gets no air flow. It has survived two Phoenix summers without cutting out or shutting off even once due to thermal issues [ Joseph  Aug 18, 2016 ]
You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your factory system. They will be able to pull up your vehicle and see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Kenny  Jul 05, 2016 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Krissy  May 24, 2016 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Kenny  May 23, 2016 ]  Staff
If your limited on space to mount a amp the Ktp is a awesome little amp , but if you already have the Mvr I would just use it . Although when mounting the KTP you don't have to run a big power cable ,you can just use the supplied wire with the ktp and wire it to your fuse panel . I have one running 4 alpine 6.5 in a GMC Sierra and think it's a great little amp ,it's compact and sounds great. [ Scott  May 04, 2016 ]
You can go big amp get get better options and maybe a few more watts, but this thing is great because you can hide it easily and it packs alot of power... I love mine.. Its alao easier to install because you can on alot of cars hode it behind the main stereo deck and tap i to all your speaker wires and power wires without havekng to run new wireing.. [ KELVIN  May 04, 2016 ]
You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your factory system. They will be able to pull up your vehicle and see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Kenny  Apr 29, 2016 ]  Staff
For additional details on installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on how everything connects and what you will need for an installation in your vehicle. [ Kenny  Apr 22, 2016 ]  Staff
I definitely recommend using whatever crossovers came packaged with your JBL speakers. They are made to work with the provided midbass & tweeter specifically. You can still use the HPF setting on the Alpine power pack if the JBL midbass drivers are not rated to play the deeper frequencies. I hope that helps! My Bio: [ Ryan  Mar 04, 2016 ]  Staff
I bought this product and had enough room under my front seat to install it. I had to remove the seat to do so but it worked great! [ JOHN A  Jan 19, 2016 ]
You can mount it in your glove box [ REYNALDO  Jan 17, 2016 ]
Hi Craig, First, I didn't put this in a Jeep Wrangler so I am not sure of the landscape you have, but I did put it in both a 2005 and 2010 Toyota Corolla, which may have a smaller interior than the Wrangler. It's a great little amp and I had multiple mounting choices: 1) behind the dash right under the Pioneer head unit I installed (chose this option), 2) in the console near the shift lever, 3) under/behind the glove compartment. It's small and can easily be held in place with a couple nice sized zip ties. Coupled with the pioneer, it made a huge difference in the Corolla's. I would buy this again. All the best! Kent [ Kent  Jan 16, 2016 ]
Yes I have been pleased with the balance in sound. Mine is paired with an alpine stereo and many people say they are impressed with the sound. I'm not an expert but I selected it based on a recommendation from a crutch field advisor and since it is their expertise, I feel it is based on a broad base of knowledge and I have often been happy I took their advice. I hope you find the best choice for your investment. [ Amy  Jan 05, 2016 ]
yes. it works fine just be sure to adjust the output. [ THOMAS  Dec 22, 2015 ]
Mario, I bought this amp and like it. I do not know if the connectors would be plug and play to your stereo deck. Look at back of this amp and back of your stereo (on-line) and the cables provided to see if you'll be able to plug and play. Hope it helps, Dave [ David  Dec 22, 2015 ]
You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your system. They will be able to see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Kenny  Dec 21, 2015 ]  Staff
It will work with any head unit [ Robert  Dec 21, 2015 ]
The 'U' version of this amp is universal so it will work with any head unit. It can be wired for either line level (via RCA cables) or speaker level inputs. The sister product KTP-445A is the one that has specific coupling with the Alpine head units. [ Richard  Dec 21, 2015 ]
You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your system. They will be able to see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Kenny  Dec 21, 2015 ]  Staff
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Krissy  Nov 13, 2015 ]  Staff
In unbridged mode (4x45W) connections are the same for 2 to 4 ohms. The amp is current limited so power output is the same with either. In bridged mode, (2x90W) this should only be used when driving 4 ohm speakers. [ Richard  Oct 14, 2015 ]
i don't know...however l bought one 1.5 yrs ago for my bike...l upgraded my speakers and needed more output...and got it....even at lowest level my wife says its too loud, lol.... [ William  Oct 12, 2015 ]
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Krissy  Aug 13, 2015 ]  Staff
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Krissy  Jul 10, 2015 ]  Staff
I installed in Honda Pilot using stock speakers (cheap) and no issue with unwanted vibration or rattling. Differetn vehicles, so prob not direct comparison. but still a decent amp for the money. [ Paul  May 22, 2015 ]
I Installed it in a jeep xj so my input would not be much help. Handy unit works well. [ KOLE  May 22, 2015 ]
I put mine in a 2007 GTI with factory speakers and it worked great. You should have preamp outputs but I'm unsure [ ALEX  May 22, 2015 ]
IT doesn't matter what you hook it to. Simply connct the speaker wires. The head unit options are irrelevant [ DAVID  May 22, 2015 ]
Hey James, I personally haven't, but I don't see why you couldn't. The sync shouldn't make a difference because there should still be all the basic wires needed to hook it up. What I would do is get behind your head unit and see what you have to work with. If you can identify all the needed wires you should be good to go. [ JANET C  May 22, 2015 ]
I don't know. [ LEONARD  May 12, 2015 ]
If you look at the specs on the this products page you will have your answer. [ WESLEY  May 12, 2015 ]
It is bridgeable, there are small switches on the back to select HP frequency and 2/4 channels [ Christopher  May 12, 2015 ]
I put mine into my 2007 Chevy Colorado and It was a very easy install. Basically all I had to do was cut and splice the unit in. It is even easier if you have an alpine unit as you can just plug it in. But all I did was cut the wires coming off the stereo and solder them to the input on the amp and then solder on the wires going to the speakers to the output. Then I just found a nice spot in behind the stereo and ziptied it down. It also provides a heck of a lot of power for its size I can really have my bass up more now and get much less distortion at higher volumes. [ JANET C  Apr 13, 2015 ]
No, but I have it in my 1990 Jeep YJ. It will work in any application. I know it's a popular solution for Harley's as well. I've been very happy with this tiny little amp. It's quite impressive considering the small size. [ ERIC  Apr 13, 2015 ]
I forwarded your question to an Advisor and they responded with the following: You would still need the HU harness, while the Power Pack harness will plug in to the radio, the HU Harness plugs in on the other side of the Power Pack If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Apr 15, 2015 ]  Staff
What kind of problems will i encounter. I purchased a 2014 Chrysler 300 with the alpine amp already installed. [ Craig  Mar 15, 2015 ]
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Krissy  Mar 15, 2015 ]  Staff
yes you can, but don't use anything else on that circuit, including cig lighter! [ David  Dec 22, 2015 ]
This DOES NOT require a direct line to battery. You simply tap off of the wiring from your head unit. I used it inmmy Harley and it absolutely cranks and I i didn't have to get creative at all with the wiring. Cheers, d [ DENNIS M  Jan 26, 2015 ]
It has been my experience after using this, and many other amps, that the output voltage has a minimal effect on sound quality. You just have to turn the gain up a little on the amp. These "Amp" ratings are taken with the head unit at full volume. And if sound quality is you goal, and not just "Loud", you won't notice. Being happy with the overall sound and audio controls of the head unit is much more important. OMHO [ DAVID L  Jan 13, 2015 ]
Mine sounded like junk. I took mine out and trashed it. Good Luck! [ ANTHONY  Jan 12, 2015 ]
Thanks Tyler.. Yes, I believe I had better go to 4V or I will always know I could have had better.. Its not really that much more money anyway.. good money spent.. better amp and etc. too.. [ b  Jan 12, 2015 ]
I personally noticed a difference when going from a 2V head HU to a 4V HU. The difference isn't significant, but is noticeable. [ TYLER L  Jan 12, 2015 ]
You will get a "cleaner" sound out of a head unit with 4V pre-outs. I switched from an older head unit with 2V to a newer one with 4V using this amp and it was a noticeable difference. [ Christopher  Jan 12, 2015 ]
That depends on how much of an audiophile you are. The average everyday person will not notice the difference. I use a 2 volt output right now and have used up to a 7 volt output from an older Eclipse. Really not much of difference in daily use. Your choice in speakers is more important. [ STEPHEN M  Jan 12, 2015 ]
No, the Sound quality is the same. Incoming voltage does not change out going response. This is a great unit. I highly recomend it, due to is versatility and ruggedness. [ ALLEN L  Jan 12, 2015 ]
I can't tell you I haven't installed it yet. [ GEORGE  Jan 12, 2015 ]
Dont need to run to battery run it off your red power from vehicle harness. Dont need large guage it is not that many watts just 45watts front and 45 watts back. [ DAVID G  Jan 12, 2015 ]
to power the amp you dont need to run any wires to the battery. you want to make a 3-way connection with the yellow 12v wires coming from the cars wire harness, the back of the stereo and the one coming from the amp. hope this answers your question [ TIM  Jan 12, 2015 ]
Just solder and heat shrink the connection. It depends on your cars wiring and fuse rating. [ MARK  Jan 12, 2015 ]
Personally I prefer using the controls in the amp, and I'm very picky about sound quality. [ DAVID L  Jan 13, 2015 ]
I've used both, it can help or reduce good sound quality. Be aware if you set your low frequency (for the speakers) like trying to reproduce sub woofer sound quality you run the risk of blowing the output transistors in the power amp! [ RICHARD J  Jan 07, 2015 ]
I left the amp at full frequency since my head unit has enough control and adjustments for me. I've been very happy with this unit as it has been plenty powerful to drive my four speakers - Alpine type R components in front, Infinity Kappa in back (roll bar ~Jeep). The small size is great as I was able to completely hide this and the subwoofer amp in a very out-of-the-way place. [ ALAN  Jan 06, 2015 ]
I'm not sure which is better, since I only used the filter if the head unit. But I have been very impressed with the amp. [ ADAM  Jan 06, 2015 ]
If you referring to "Bridging" two amps together? No. If your asking if it will function as a 2 or 4 channel amp? Yes [ DAVID L  Jan 13, 2015 ]
Yes you can bridge it from 4 channels to 2 channels. Hope you enjoy it, it's a great amp. [ JAMES K  Jan 02, 2015 ]
Yes, it is bridgeable. There is a tiny dip switch on one end that allows you to select 2 channel or 4 channel mode. Also instructions for wiring either mode. [ JOSEPH  Dec 31, 2014 ]
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Krissy  Dec 26, 2014 ]  Staff
I forwarded your question to an Advisor and they responded with the following: The PAC OS-5 Factory Integration Adapter has an external chime speaker which you'll need to mount facing downward towards the floor so it's away from you. Since it's built in to this module it won't be affected by your separate amplifier. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Dec 23, 2014 ]  Staff
I'm sorry, I wish I knew for sure. I had it professionally installed. I believe it ran off the head unit's power. Hope you get figured out and enjoy it!!! [ JAMES K  Nov 16, 2014 ]
We have two of these, one in each car. I've run both off of the factory head unit wiring. [ MICHAEL  Nov 16, 2014 ]
Yes you can use the head unit power line. That is how it is supposed to wire. [ DANIEL  Nov 15, 2014 ]
I used the same power wires that go into the HU. I believe you can do it either way though. [ John  Nov 15, 2014 ]
HI, You need to run a wire from the battery to the amp. It requires a thicker gauge wire and a inline fuse. When i purchased this i also got a amp wire kit. This is a great amp and no problems with it. [ ALAN  Nov 15, 2014 ]
It depends on the amperage handling of your head unit. If it can meet the specs of the alpine then you can, of course you still would need a fuse in line. If it canonot supply the amperage, then you would have to run a line to your battery with an in line fuse. [ BRIAN  Nov 15, 2014 ]
Brendan, I am fairly certain that you should still be able to use your current Sub set up. You may however need to tweak some of the settings on it after installing the Alpine. Good luck! [ DENNIS M  Nov 03, 2014 ]
I use this amp to power some door speakers up front. I still have my self-powered sub in the back. Just pass the speakers you want thru this amp. Bypass it for your sub. [ JEFFREY  Nov 03, 2014 ]
In a word - yes. [ PATRICK M  Nov 03, 2014 ]
If money is not a problem I would go for a more powerful 4 channel amp. Power is important but the THD is just as important. Be sure and check the (total harmonic distortion) at different power levels. Some amps have good specs. Power wise but they get noisy when the power is increased. Hope this helped. Jackie L [ JACKIE L  Sep 14, 2016 ]
ben this amp is well sutited for smaller speakers. it performs well with 6x9 or smaller in set if 2each. bruce [ DEBORAH  Sep 09, 2014 ]
Thank You for your reply. [ ChadW  Jan 04, 2015 ]
I forwarded your question to an Advisor and they responded with the following: As long as you don't have the premium audio system then it will work, but it is not ideal. Your radio is not equipped with a 15amp fuse. I would recommend going with this option by Clarion. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Sep 03, 2014 ]  Staff
Josh The ktp445 that I purchased, I installed behind a Kenwood exelon on Rockford fosgate speakers. So I can't give a direct answer for this application. I have however used this method to hook a JL 1500 mono amp to a factory head unit and it seems to function just fine. I guess it would depend on the quality of the hi to low pass converter that you use. I would not advise hooking a ktp445 to a factory speaker though. As it probably would not last very long. Over all, on a set of aftermarket speakers, as long as the gains on both converter and amp are set correctly. Should be OK. Give it a go man. [ DERIC  Aug 17, 2014 ]
Yes you can, and no sound compromise, make sure that your vehicle' speakers would hold the power output from the power pack, the little thing is small in size but deliver plenty of power. Goodluck! [ FRANKLIN  Aug 16, 2014 ]
I apologize I can't answer your question mine is still sitting on the bench waiting to be installed. [ GEORGE  Aug 16, 2014 ]
I'm afraid I don't have an answer for this. I wired mine to a radio that had the rca outputs. [ LEONARD  Aug 16, 2014 ]
I was able to use the RCA but I see no reason you could not use line level. I don't believe the sound quality would suffer. I'm very happy with this amp. It fit into the space I had to work with (it's about the size of an average TV remote) and is very adequate driving a pair of Alpine type R components and a pair of Infinity Kappas. [ ALAN  Aug 15, 2014 ]
You can hook up rca jacks to output..not sure how the sound quality would be.. [ MARK E  Aug 15, 2014 ]
I had no RCA units on my stock head unit. I did a pop test to make sure there wasn't an amplifier somewhere in the car that I ididn't see (there wasn't). Next, I ran a separate power line from battery to the Alpine KTP, cut the existing speaker wires from the head unit and wired directly to the Alpine KTP and then from the KTP back to the four speakers in my car. No need for line converters in my application. I ran a separate powered sub. [ MARK  Aug 15, 2014 ]
No need for anything. I cut the factory speaker wires and put this unit in line. Factory worse in and out. Sound is fantastic and no distortion due to ability to set frequency on amp. Would buy it again [ DAVID  Aug 15, 2014 ]
You could do that but I wouldn't reccomend it the signal loss is going to be substantial plus a whole slew more hardware to find a place to tuck away I think you'd be better off getting a small amp with line level input [ DAN  Aug 15, 2014 ]
I strongly urge you to ground the amp to bare metal in the car chassis. Not familiar with the GMOS, but the amp should be the last thing on the way to the speakers themselves. [ JOSEPH  Aug 07, 2014 ]
After the adapter for sure. Rule of thumb is to have all power and grounds, especially grounds, to be common, or from the same source. I use distribution blocks that disperse the power and ground grime one source for all audio related gear. Really helps ward off noise. [ ADAM D  Aug 02, 2014 ]
I have mine wired like any other traditional amplifier. In that sense no other harness needed. I am using a kenwood hu. [ DEREK L  Jul 29, 2014 ] tap into the power and ground on the existing harness then use either rca or speaker line for input...then hardwire the speaker output...just like any other amp would be... [ KELVIN  Jul 29, 2014 ]
I forwarded your question to an Advisor and they responded with the following: The front and rear outputs have independent high pass filter settings, so you can adjust them independently. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Jun 25, 2014 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Jeff  Apr 25, 2014 ]  Staff
I'm running my amp off of same power lead as my HU but only running a pair of tweeters. You have to make sure the wire gauge and fuse can handle the combined power rating of all components. [ PETER J  Apr 26, 2014 ]
It's powered right off of the head unit power feed. So you shouldn't have to run another wire to the battery or add anymore fuses. [ MICHAEL H  Apr 24, 2014 ]
The goal is to have a fuse between the amp and the battery that's 15 amp or better. So the radio fuse in the fuse box is an option if its high enough. [ JEFFREY  Apr 24, 2014 ]
Hi Maurice, This is the detail in the manual. I went with option A a year ago and have not had any problems at all. It works great. Battery Lead (Yellow) There are two options: a. Connect battery lead to OEM radio fused circuit The OEM radio circuit has a fuse to protect your vehicle's electrical system in case of a short circuit. Do not connect the battery lead to the OEM radio circuit if the fuse rating is less than 15A. b. Connect battery lead directly to BATT+ Be sure to add a 15A fuse (sold separately) as close as possible to the battery's ( +) terminal. [ JEFFREY  Apr 24, 2014 ]
My install guy powered the alpine amp directly from the stock radio power line. I have four Polk 65 watt max speakers connected to my alpine amp. It more than doubled the output. He was impressed with the amp, output and it's an Alpine. [ CESAR  Apr 24, 2014 ]
No need to add another fuse. Just plug and play [ DEREK L  Apr 24, 2014 ]
I forwarded your question to an Advisor and they responded with the following: This amplifier is 2-ohm stable and the output would be 45 watts. The amplifier has a regulated output which is why the 2-ohm output isn't greater than the 4-ohm output. It should work just fine with the 2-ohm factory speakers. When used in vehicles with a factory amplifier, the factory amp will need to be bypassed (this may result in lost speaker channels, if factory amp has more than 4 channels). The increase in power may result in a louder warning chime in certain vehicles. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Mar 16, 2014 ]  Staff
Thanks for your question. For information on selecting the best amp I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Krissy  Feb 12, 2014 ]  Staff
You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your current system. They will be able to pull up your gear and see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Jeff  Jan 16, 2014 ]  Staff
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Jeff  Dec 16, 2013 ]  Staff
If you buy speakers and do not change your head (stereo), you need to power them with a amp. This is good to power 2 front and 2 rear speakers. And is small enough to mount behind your head, instead of a normal size amp which you would mount in the trunk. [ STEVEN  Dec 27, 2013 ]
Short answer is no, this unit is not the best choice for a subwoofer amp. The amp is 45 watts by four channels, or bridgeable to roughly 100 watts by two channels. So you would need either a Dual Voice Coil (DVC) subwoofer, or two subwoofer drivers, to take advantage of both bridged channels. Also, while this is a nice amp, the crossover choices aren't really set up for subwoofer use. For a single subwoofer driver, or for multiple subwoofers wired together, you would be better off with a dedicated mono channel subwoofer amplifier. [ JOSEPH  Dec 18, 2013 ]
It ' San accessory to add s [ DENNIS  Dec 16, 2013 ]
Only if it was a very low RMS sub. It is much better suited to powering aftermarket door/dash speakers. Works great with my 4 x Polk 6 1/2 db series. [ DANIEL  Dec 16, 2013 ]
jerry this unit far exceeded my expectations. had unit installed by pros. works great. b mcintyre [ DEBORAH  Dec 06, 2013 ]
I've installed this in a 2013 gmc sierra [ DEREK L  Dec 05, 2013 ]
Not in a Tundra but in a 2006 Honda Accord LX with an Alpine head unit. It fit nicely behind the dash and packs a big enough punch for my listening. My family can here me inside the house when I pull in and jamming to a good tune! [ JOSHUA  Dec 05, 2013 ]
I have not done one in a Tundra, but I put this in my Harley with polk DB speakers. IT PACKS POWER!!! I was able run it without even bridging it and it cranks two 6.5s with deeper bass and crystal clear mids and highs. I used do custom installs for a living. This amp would've fit any where and made my life a lot easier. It's compact but packs intense power. It would be a great add on to any factory stereo. Feel free to email me with added questions. Cheers, Dennis [ DENNIS M  Dec 05, 2013 ]
Nope. Mine went in VERY tight quarters in a '94 Corvette. I'm DELIGHTED with it! [ ANTHONY  Dec 05, 2013 ]
No. In a Jeep Wrangler. Easy to install [ LEWIS C  Dec 05, 2013 ]