Alpine KTP-445U Power Pack

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

Item #: 500KTP445U

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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

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

Hands-on research

What's in the box?

Download owner's manual

  • Head Unit Power Pack (15A 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 (En/Fr/Sp)
  • Limited Warranty card
  • "Thank You" letter

Scratch & Dent items may be missing non-essential accessories. In some cases the manufacturer's accessories have been replaced with generic equivalents.

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.

  • Because of its high-powered amplifier design, the Alpine KTP-445A does require that a separate +12V constant power wire is run to the battery with a separate inline 15A fuse in vehicles with lower than a 15A fuse protecting the factory radio. Check out the "Accessories" tab for wiring kit.
  • 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.

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

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Alpine KTP-445U Power Pack Reviews

Average Customer Review:

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

Written By JT, Georgia on Monday, March 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

Written By Isaac, Wisconsin on Tuesday, March 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

Written By WRX owner, Nevada on Wednesday, January 07, 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

Written By super soobie fxt, ny on Sunday, December 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

Written By SYates, Orlando, FL on Sunday, December 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

Written By xJoeMama78, Chandler, AZ on Tuesday, December 09, 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

Written By Cliff, Arizona on Wednesday, December 03, 2014

Crutchfield Customer Review (What's this?)

Compact power pack. Easy to mount under the dash


Written By Anonymous, Bardstown, KY on Monday, November 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

Written By tom, Denver, CO on Monday, November 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

Written By John, Chesterfield, VA on Friday, October 03, 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

Written By schambo, Bergen County, NJ on Monday, September 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

Written By phaelax, ohio on Wednesday, September 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

Written By Bob L, Cranston, RI on Friday, September 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

Written By Joe, Wesley Chapel FL on Friday, September 05, 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

Written By James, Hilton Head Island, SC on Sunday, August 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

Written By Stan, michigan on Tuesday, August 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

Written By Mack, LaGrange, IN on Tuesday, July 08, 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

Written By Scott, Ky on Monday, June 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

Written By RMJ, Fredericksburg,VA on Tuesday, June 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)

Written By Juan, on Monday, June 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

Written By Anonymous, st. peters, mo on Saturday, June 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

Written By Hit the road, Moreno Valley, CA on Friday, June 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!

Written By Rob H., Milner, GA on Tuesday, June 03, 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

Written By Harley rider, Chickasha, OK on Saturday, May 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

Written By John, Northeast Ohio on Tuesday, May 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...

Written By MisterMike559, Sanger CA on Saturday, May 03, 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

Written By White Wolf, Arlington, TX on Monday, April 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

Written By Jason, Portland, OR on Friday, March 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!

Written By Russ, AR on Tuesday, March 04, 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

Written By manooti, east stroudsburg PA on Tuesday, January 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.


Written By BJK, OKC on Saturday, January 18, 2014




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

Written By Juan, Chicago Heights on Friday, December 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

Written By B-RAD, Indianapolis, IN on Friday, November 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.


Written By Kevin, Arcadia,WI on Tuesday, November 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

Written By Butchie, Washington on Tuesday, November 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

Written By Tim K, Sanford, NC on Wednesday, November 06, 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

Written By Anonymous, metairie la on Tuesday, October 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


Written By CalN, Bloomington, MN on Sunday, October 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!

Written By Mike K., Chicago area on Wednesday, October 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

Written By Anonymous, Altoona, PA on Sunday, October 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

Written By ch, kentucky on Monday, September 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

Written By wortman, gaston, sc on Monday, September 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.


Written By Jon, San Diego, CA on Friday, August 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

Written By Super fish, West michigan on Saturday, August 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.


Written By John, Bethany Ok on Sunday, August 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

Written By Anonymous, GA on Saturday, August 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

Written By tutman, michigan on Tuesday, July 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

Written By Justin S, Indianapolis, IN on Sunday, July 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!

Written By PatrickM, Plano, TX on Saturday, June 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

Written By JimB, Lake Stevens, WA on Thursday, June 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

Written By Josh, Vail, AZ on Monday, June 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

Written By RobertP, Clemmons, NC on Saturday, June 08, 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

Written By tomg, WI on Monday, June 03, 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

Written By Boz, Blue Ridge Summit, PA on Tuesday, May 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!!!

Written By chaces1, NYC on Thursday, May 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

Written By Jeremy, Indiana on Wednesday, May 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

Written By Mike, Western PA on Sunday, May 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

Written By angryshuna, Boston, MA on Tuesday, May 07, 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

Written By gasman, michigan on Monday, May 06, 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

Written By Harley, USA on Tuesday, April 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

Written By Aaron, Indianapolis, IN on Sunday, April 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.....

Written By Patrick, Chester, VA on Sunday, April 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

Written By Steven, Charleston, WV on Saturday, April 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+

Written By Toddman, N.Tx on Saturday, April 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


Written By Anonymous, clinton md on Monday, April 08, 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

Written By wedu22, Groton, CT on Monday, April 08, 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

Written By Anthony, Houston, Texas on Saturday, March 09, 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.

Written By 9859limited, Massachusetts on Sunday, February 03, 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

Written By Anonymous, Washuington state on Monday, January 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)

Written By mobrien1968, Long Island, NY on Thursday, January 03, 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).