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Infinity Kappa K4

4-channel car amplifier with Bluetooth® connection — 100 watts RMS x 4

Item # 108K4

Infinity's Kappa K4 4-channel car amplifier can supply a couple of sets of high-performance speakers with 100 watts...

Infinity's Kappa K4 4-channel car amplifier can supply a couple of sets of high-performance speakers with 100 watts...

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About the Infinity Kappa K4

High tech and stylish

Infinity's Kappa K4 4-channel car amplifier can supply a couple of sets of high-performance speakers with 100 watts RMS each — good news for all you music fans out there. Even better, you can stream music directly from a Bluetooth device to this amp, while its built-in processing restores the excitement in your music that data compression removes. Plus, the dancing, signal-level LEDs on the cover add to the amp's high-tech look and overall coolness factor.

High tech and stylish

Infinity's Kappa K4 4-channel car amplifier can supply a couple of sets of high-performance speakers with 100 watts RMS each — good news for all you music fans out there. Even better, you can stream music directly from a Bluetooth device to this amp, while its built-in processing restores the excitement in your music that data compression removes. Plus, the dancing, signal-level LEDs on the cover add to the amp's high-tech look and overall coolness factor.

Connectivity is the name of this game

You can stream music from your compatible Bluetooth device directly to the K4, for convenient, wireless play that bypasses your car's radio. The amp's preamp outputs let you connect a subwoofer amp, like the matching Infinity Kappa K1000 or Kappa K600, for better-sounding bass in your music. The Party Mode feature allows up to three different sources to stream, so more people can join in the fun. The included wired remote gives you handy controls for Bluetooth streaming, hands-free calling, Party Mode, and Clari-Fi™ signal processing.

Powerful and versatile

Need some bass power? You can switch the K4 into bridged mode and drive two subwoofers with 250 watts RMS each. A high- or low-pass filter matches the amp's output to your speakers, increasing the efficiency of the system. The Kappa K4 can accept low- or speaker-level inputs so it'll work in almost any system, and Infinity includes RCA-to-speaker wire adapters so you'll make the right connections.

Decompression saves the sound

Downloaded digital music and streaming services apply data compression to their files so you can store more of them on your devices, but compressed music sounds noticeably duller than uncompressed files. Harman's Clari-Fi™ sound restoration technology improves the sound quality of your digital music by analyzing the data and then reconstructing the parts that were removed during the compression process. You get crisper highs, increased dynamics, and clearer vocals.

Infinity Kappa K4

Kappa K4 input and control panel

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Product highlights:

  • 4-channel car amplifier
  • 100 watts RMS x 4 at 4 ohms (120 watts RMS x 4 at 2 ohms)
  • 240 watts RMS x 2 in bridged mode (4-ohm stable in bridged mode)
  • separate variable high- and low-pass filters (32-320 Hz, 12 dB/octave) on front and rear channels
  • wired remote unit has controls for Bluetooth streaming, hands-free calling, Party Mode, and Clari-Fi signal processing
  • preamp inputs and outputs
  • speaker-level inputs (speaker wire-to-RCA adapters included)
  • fuse rating: 30A x 2
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • 10-1/4"W x 1-3/4"H x 6-15/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee
  • MFR # K4

What's in the box:

  • 4-Channel amplifier
  • Four 30A ATO fuses (2 installed)
  • Control panel with attached 19.5' cable
  • Control panel flush mount sleeve
  • Control panel mounting bracket
  • 2 M4 x 10mm bracket screws
  • 4 Bare wire-to-RCA adapters
  • Remote plug (Euro or Phoenix connector)
  • 4 Mounting screws (M4 x 52mm)
  • Quick Start Guide

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Infinity Kappa K4 reviews

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34 reviews

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Highly recommend

Bradley from Lafayette, IN on 7/7/2018

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Great amp, would highly recommend. Purchased this amp because of the Bluetooth capability, which saved me from having to splice into the current factory radio signal.

Pros: Realtime level indicators are really cool. Bluetooth!

Cons: Clear-fi signal processing enhancements DOES get sent via the 'pre-out' outputs, which seemed misleading. This can cause other amps down the chain to distort.

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1 of 1 found this helpful

Best Amplifier for 4 channel

Caleb from Wichita, KS on 6/26/2018

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I used this on my 2009 Pontiac G8 GT, and I have never been so happy with an amplifier in my life. The bluetooth remote is so quick and useful to pair your phone in a car, yet the G8 doesn't even have bluetooth. The bluetooth was a major upgrade to the aux chord. The amp does everything it says and more. I paired this amp with 4 polk speaker each running 100 rms and tweeters in the front. Never heard an amp sound so good through speakers.

Pros: -Sounds great -Clarity -Heats up very little -Looks great -Active EQ is awesome

Cons: Absolutely none

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1 of 1 found this helpful

Infinity Kappa K4

Crutchfield customer from Cheyenne, WY on 6/5/2018

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Easy to install. Hooked up 2- 6x9 ,2- surface mount speakers under front seat and a powered sub . The Sound Is Excellent. Can turn it up and and it's Clear as can be . Worth the money

Pros: Easy to install. Sounds Great

Cons: None

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2 of 3 found this helpful

Great amp

Nick from Arlington, TN on 5/20/2018

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Can't ask for better sound. I could pierce my eardrums if I wanted. Turn it up as loud as I can take it and it's still crisp and clear. Only issue is the amp cuts out every now and then and I am left with just my subs. No clue why. It is in a great location with plenty of room to breath.

Pros: Can't ask for better sound. I could pierce my eardrums if I wanted. Turn it up as loud as I can take it and it's still crisp and clear.

Cons: Amp has cut out a few times when really playing it hard. It's in a good location with plenty of room to breath

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3 of 3 found this helpful

Infinity Kappa K4

John j from Poughkeepsie, NY on 5/4/2018

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Awesome amp

Pros:

Cons:

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1 of 2 found this helpful

Improved Sound

julius from National City, CA on 5/3/2018

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Fast delivery and well packaged. Product exceeds my expectations so Crutchfield has quality product. Thank you!

Pros: Good quality service, customer satisfaction guaranteed

Cons: None experienced yet

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2 of 2 found this helpful

Loud and Proud

Brian from Baltimore, MD on 5/1/2018

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It's loud it's functional and super crisp. I haven't used the Bluetooth yet, but the bas from this running my front and rear speakers is awesome! Infinity makes nice audio gear, so i knew this would be top notch, but i'm blown away.

Pros: Loud audio meters

Cons:

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3 of 3 found this helpful

Infinity Quality! 5 star / A+

James from Sunbury, PA on 4/26/2018

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Excellent amp. I've always steered away from 4channel attempts but as I grow older I don't need the high power of a 2 channel amp anymore. And this amp actually still has high power. Crystal clear! Compact and just what I needed! Easy hook up with Infinity Quality connections! Also very appealing to the eye!

Pros: Excellent sound, small footprint, very dynamic configuration options.

Cons: Absolutely none

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3 of 3 found this helpful

Infinity Kappa K4

Nicholas from Canonsburg, PA on 4/14/2018

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I purchased this to replace a Zapco ST-4X P. The Zapco was fine, but wouldn't fit in the small area behind my seat that I wanted to use. So i decided to give this guy a try. Wow, is it awesome. First, it's the smallest amp with this kind of power that I've ever seen. This provides a lot more flexibility in placement. This is enhanced by the fact that all the connectors are on the long side, so you don't have to add connector lengths to the unit length (the failing of my Zapco). Sound quality is fantastic, and it had all the controls I needed. It has a direct passthru for the rear channel, and I would have preferred a 4-channel sum going to my sub. Now if I turn the rear speakers down at the head unit the sub gets less signal. But most other amps I looked at had the same so I can't ding a star for that. I thought the bluetooth streaming would be worthless, but instead it's been a godsend. My head unit doesn't put out a flat response curve, and with only three bands I can't do much to correct it. So until I can afford a sound processor, I can use my phone with a $3 app that has a 11 band equalizer and stream directly to my amp for incredible sound. The compressed music processing seemed worthless to me. I turned my back speakers down as they're fill (and very efficient). The processing turned them back up and they drowned out the fronts so it was unusable. Blah. Still, great sound quality, form factor, and more features than compe

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2 of 2 found this helpful

Infinity Kappa K4

Crutchfield customer from Atlanta, GA on 4/10/2018

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Excellent amplifier. Outstanding for the price.

Pros:

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2 of 2 found this helpful

Great amp at a great price

Chris from Cantonment, FL on 4/4/2018

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This product has exceptional amplification properties, amazing clarity, great separation, and a price anyone would happily pay!!! This amp rocks!!

Pros: Small footprint Superb amplification Amazing tuning response

Cons:

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2 of 2 found this helpful

One Fine Amp!

Kent from Loveland, CO on 3/24/2018

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I couldn't believe how much difference a high quality amp made! The K4 packs over twice the power of my old amp and the clarity is amazing. I thought the bass response was limited by my speakers, turned out that was not the case. I am a happy customer.

Pros: Power, clarity, bass drive, small size.

Cons: None.

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1 of 1 found this helpful

Fantastic product.

Laurence from Riverside, CA on 3/11/2018

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Although I have not installed the amplifier, I am confident that I will be very satisfied with it. I am an Infinity product loyalist. I have 98% percent Infinity products. Crutchfield did an excellent job assisting me gathering my information and they all are technical very knowledgeable. I have also become a Crutchfield loyalist.

Pros: Great clean sound and plenty of power.

Cons: None so far.

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1 of 9 found this helpful

Amazing!

Marty from North Liberty, IA on 2/26/2018

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So much power! Love this amp!

Pros: So much power and flexibility! Love the price at Crutchfield!

Cons:

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2 of 2 found this helpful

Infinity Kappa K4

Greg from Abbeville, SC on 2/18/2018

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Love this amp!

Pros: Crisp highs, tight mids, rich bass!

Cons: None

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3 of 3 found this helpful

Great sound poor customer service with Infinity

Ryan from Denver, CO on 2/14/2018

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I put this amp with some Alpine R speakers, it thumps. Installation was mostly easy I am coming from a stock radio so I had to use the speaker wire to RCA adapters. The Adapters suck and I had one that had a stripped out screw. Infinity's customer service was horrible if it wasn't for Crutchfield I wouldn't still have this amp in the car they came through with some replacement wires that were so much better. I have been using the blue tooth feature on this a lot, it works great. The Clari-Fi signal processing helps give nice crisp signals to help with internet loss. I think it works good. I like the fact that I can run wires out to a second amp so that I will be able to hook up a sub.

Pros: Clari-fi signal processing is great the blue tooth feature works well

Cons: Infinity's customer service sucks Speaker wire to RCA adapter

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2 of 3 found this helpful

Infinity Kappa K4

bernard from Grand Portage, MN on 2/10/2018

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This amp is tiny but powerful. It fits in small places and it brings out the best in my aftermarket speakers. I had it installed under the cargo floor of my Kia Sorento. It fit perfectly. I am very happy with this amp. If you are using the factory head unit make sure to get a Line Out Convertor.

Pros: Works as I expected

Cons: No issues. Great product

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2 of 2 found this helpful

Kappa K4 rocks!

BB from Sooner Land on 12/9/2017

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Installed in 2016 Chevy Express van with stock cd stereo. Paired with Kappa component 6.5 and JL 10 sub. Installed under passenger seat with speaker level inputs. Oh my! WARNING! 1/2 up the volume knob will cause a permasmile and minor hearing damage. Face-melting power in a small package and whatever witchcraft ClariF is, no amp should be without it. Bluetooth call features kick butt and music from your phone plays and sounds flawless with ClariFi tech. 120w x2@2ohms up front, 240wx1 to the sub behind the driver seat. It is sound perfection.

Pros: Sound quality, power, features, size, speaker inputs, ClariFi tech, built-in bluetooth, sale price.

Cons: Mounting the wired remote panel will require permanent alterations to interior. Big hole or small hole depending on which of the 2 mounting brackets u use. Why not make it a wireless remote? It already has bluetooth. ??

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2 of 2 found this helpful

Infinity Kappa K4

Michael from Clanton, AL on 12/5/2017

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This amp is being matched with a pair of infinity 62ix speakers. Sound is crisp and clear. Easy install. Price was amazing. On sale. Can't beat that. I would have given it a 5 star but I think the connection for the turn on wire would have been more robust if they had put it where the power and ground wires are located.

Pros: Sounds clear. Powerful. Small foot print. Makes speakers come to life. I would recommend this amp to anyone wanting to run all four of your speakers.

Cons: Turn on wire connector should have bee a acre down connection like the ground and battery wire. Other than that, it's a great product.

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3 of 3 found this helpful

Infinity Kappa K4

Crutchfield customer from Tucker, GA on 11/16/2017

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sounds and works amazing. would buy again. perfect match for my kappa speakers

Pros:

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2 of 2 found this helpful

Great Features and Value

Todd from Brentwood, CA on 11/13/2017

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Very easy to install. I have a convertible and the hands free i am told by the people i call sounds like a regular car to them. The bluetooth features made it really cool to install in an older car and give it updated features. Crystal clear audio.

Pros: Easy install.

Cons: I wish they would put the full manual in the box.

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1 of 1 found this helpful

Infinity Kappa K4

jim from Rocky Mount, NC on 11/12/2017

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Great little powerful amp,sound quality is amazing!Would by another one from Crutchfield.They have the best customer service and prices around,and shipped extremely fast!!

Pros:

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1 of 1 found this helpful

Good for the price...

Sam from Denver, CO on 10/18/2017

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This amp has was an easy install. Everything was marked well and the directions were as needed. It sounds great. Only drawback (which is why the 4 stars) is that the Bluetooth for phone hands free does not have much volume to it. IPhone 6s plus volume is at max and you have to pay close attention to hear it. Playing iheart radio or similar through Bluetooth, the volume is not as loud as the factory radio/cd player but almost satisfactory. 4 speakers are infinity also. There is no volume adjustment for Bluetooth other than your device.

Pros: Sounds good. Much higher volume. Has Bluetooth when I did not have it before.

Cons: Needs some type of equalize on it to make it sound great. Needs Bluetooth volume adjustment

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4 of 4 found this helpful

My review

Michael from Charleston, SC on 10/15/2017

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It gave my Focal speakers all the power they needed plus some. It's so loud in my car now, I can barely turn it all the way up ????

Pros: Awesome

Cons: None

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5 of 5 found this helpful

Awesome amp!

Jake from St. Croix Falls, WI on 10/9/2017

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What an amazing amp! Works perfectly with the kappa speakers. Once they are plugged in it's almost perfect right off the bat. A few tweaks and your listening to speakers that have plenty of power and great sound!!!

Pros: Easy set up, great components.

Cons: None!

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2 of 3 found this helpful

What you would expect from an item with the Kappa name

Crutchfield customer from Riverside, CA on 10/2/2017

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This amp is awesome. It outputs great, clean sound, and the built in Clari-Fi feature makes a huge difference in the sound quality, even for 192 kbps streams. I haven't tried connecting to it directly via Bluetooth since my head unit has features that I don't want to bypass, but it's neat that option is available. The controller is pretty bulky, and doesn't have a gain control setting on it, so I don't think it useful in my use situation, but if you are someone who plans to connect to it with Bluetooth, I could see it being something you'd like to have. Also, I like that is has a remote line out, even though it is also something I don't use as I had already set up a relay. The unit looks great, it's foot print is small, and it puts out a nice power level. Especially if you have it powering some Infinity Kappa speakers with only 2 Ohms impedance.

Pros: Great look Small footprint Remote line out 120W RMS x4 @ 2 Ohms

Cons: Controller isn't super useful, especially considering its large size

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1 of 1 found this helpful

great product at great price

eric from Bowie, MD on 9/30/2017

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gave my morel speakers the power they needed....doubled my power and with less distortion

Pros: ease of install...i can't use all the features..small size big sound

Cons: none

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1 of 1 found this helpful

Excellent! Plenty of power

Harrison from Woodstock, GA on 9/7/2017

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Excellent amplifier! Replaced the stock speakers and amplifier in my 2014 Tundra and couldn't be happier. The speaker-level RCA adapters made this install incredibly easy and doesn't sacrifice sound quality. I was able to keep my stock HU without having to purchase any type of processor or summing appliance. Bluetooth, ClariFi, and Party Mode are cool features, but I simply don't use or need them. I did switch on ClariFi briefly because I was curious, but was not impressed enough to use it regularly. I would suggest either using it or NOT using it, but not both. I had already tuned the amp when I turned it on and it changed the whole dynamic of the tuning. So if you're going to use it then tune your amp with it ON and then leave it on. Overall, I'm very pleased with my purchase and would recommend it to anyone looking to add some serious power to your speakers.

Pros: Adds plenty of power to my speaker upgrade Very easy install and tuning Incredibly small form factor making placement very easy Convenient RCA adapters

Cons: None

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5 of 5 found this helpful

Awesome!

Crutchfield customer from Kentucky on 9/3/2017

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Badass amp! I appreciate Crutchfield for recommending it!

Pros:

Cons:

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4 of 4 found this helpful

Kappa K4 as subwoofer amp.

Eric from Los Alamos NM on 9/1/2017

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I bought this amp to run in double bridge mode to power a bass reflex sub housing two 6" woofers, side by side. I couldn't be happier- the bass is tight, there's enough power to destroy the sub, and I used the dual crossovers as low end filters to attenuate the low frequencies the sub just can't reproduce. Plus this amp can respond as high as you want, unlike a monoblock. Tight, powerful bass that's more than enough for my Toyota Tacoma!

Pros: Small footprint. Enough power to be used as a sub amp. Dual crossovers.

Cons: Could use a "summed" input switch for the RCA's. Used splitters. The crossovers were perfect for me, but surprised not to see a frequency multiplier on one of them.

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1 of 3 found this helpful

This thing is the BOMB!!

Jimmy from Coatesville, PA on 8/30/2017

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Exactly what the doctor ordered!!! I installed in a 1966 chevelle with a classic looking head unit. The head unit was not great, didn't give great sounds and couldn't Bluetooth at all. I wanted to keep the stock classic look and this was a perfect option. It's small and slim enough to install under a bench seat with plenty of clearance and breathing room. I paired this with a set of Focal 6x9 and configured for two channel. What an amazing difference this unit makes. It can be linked to multiple phones and allow people in the car to share their music. It sounds fantastic and it loud enough to hear quality music with open windows and racing exhaust!! If you don't have a lot of stereo install experience, it doesn't matter... very simple, plug and play. I'm thrilled with the install and the outcome and can't wait to cruise with some new tunes and the windows down.

Pros: Small and slim, fits under seat, easy connections and instructions are simple for a less experienced installer. Great option for classic car that needs a boost and compatible with Bluetooth

Cons: Mounting screws are great for installing on a box, but need something more robust if mounting to floor or in trunk.

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4 of 4 found this helpful

Infinity Kappa K4

Big Al from Cape May Court House, NJ on 8/4/2017

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Purchased k4 amp , powering kappa 693.11i in boxes for rear of truck ,using kappa 682.11cf in front doors, added infinity bass link . Truck is a virtual concert hall .Excellent sound . Couldn't be happier. Thanks Crutchfield. I would match this with almost anything out there .

Pros:

Cons: n/a

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5 of 6 found this helpful

Infinity Kappa K4

Brian from Wausau, Wisconsin on 3/6/2017

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AMAZING .... Infinity has done it again!! Clean appearance, very nice hardware, crisp/ clean power!! Recently I picked up a " Black Ice" amp, ended up getting rid of it because of it's ridiculous underpowering performance.... setting up my infinity resulted in the exact opposite! Add that to the new features it has, I will never make the mistake and stray from the excellence I've always found with Infinity ! Also, Crutchfield is the most amazing company to work with as well ! From the quality products, AMAZING communication, FAST shipping, and the BEST hands down customer ( technical ) support that every other company should be taking notes from !! I am excitedly awaiting my next purchase, which will be via Crutchfield !!

Pros: EVERY SINGLE THING about this amp is AMAZING!!

Cons: I don't have enough money for another one ..... yet..??

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7 of 11 found this helpful

Infinity Kappa K4

John E. from Litchfield CT on 7/29/2016

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Crutchfield yo've done it again,I am so happy with my new stereo ,Infinity kappa k4 amp. Infinity bass link sw ,powering Alpine spr-50c speakers with a Kenwood navigation head unit running it all.

Pros: best sounding car stereo i,ve ever heard!

Cons: none.

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Product Research

Features

Overview: The Infinity Kappa K4 is part of the Kappa series of high-performance amplifiers. This full range Class D 4-channel amplifier will accept both high-level and low-level inputs. Class D amplifiers are highly efficient and compact, generating lots of power without drawing much current or generating heat. The Kappa K4 includes Clari-Fi, an audio restoration feature that improves the sound of compressed digital files. The amp also includes a cabin-mounted control panel to give you amplifier control at your fingertips. The unit comes with spare fuses, speaker wire-to-RCA adapters, and mounting hardware.

Power Output: The Kappa K4 delivers the following power output:

  • 100 watts RMS x 4 at 4 ohms (<0.1% THD+N)
  • 120 watts RMS x 4 at 2 ohms (<0.1% THD+N)
  • 240 watts RMS x 2 at 4 ohms bridged (<0.3% THD+N)

Clari-Fi: Clari-Fi is a proprietary technology that analyzes compressed digital music files and improves them in real time. Using a predictive algorithm that restores audio content that is lost during the compression process. Clari-Fi provides extra bandwidth, especially in the high frequencies, widens the sound stage, and gives vocals a natural warmth not found in compressed files.

Control Panel: The amplifier comes with a wired control panel that provides numerous features not typically found with amplifiers. It has Bluetooth technology, and an omni-directional microphone for accepting and ending phone calls from your cell phone. Party Mode lets you pair multiple Bluetooth devices for streaming music from anyone's phone. The control panel also lets you activate the Clari-Fi feature. The panel is 4-7/16"W x 15/16"H, and has a 19.5-foot cable. It can be flush- or surface-mounted with the supplied brackets.

ADAS: The Kappa K4 has an interface for the Advanced Driver Assistance System (ADAS) that can override the audio source input to deliver a message or other audio from a connected ADAS accessory. On the amplifier, you can designate which speaker the ADAS signal is output: Front left, front right, rear left, or rear right.

Protection Circuitry: The amplifier features protection circuitry for thermal overload, over- or under-voltage (<9V or >16V), and short circuits. The LED on the top of the amp glows red if the amp goes into protection mode.

Controls: The Kappa K4's controls are located on one side of the amplifier. The rotary controls require a small screwdriver (not included) to make adjustments. The amp controls include:

  • Gain: The rotary gain controls let you match the amp's input sensitivity to the output of the source unit. The input sensitivity range of the amplifier is 0.2V and up for a low-level input, and up to 20V for speaker-level input. There are separate gain controls for the front and rear channels.
  • Input Level: The Input Level switch lets you select the type of input you are using. For high-level input, there are two settings: Hi1 and Hi2. If the audio system fails to play with an amplifier connected to its output, or you get a "speaker disconnected" message on your factory stereo, set the switch to the Hi2 position. The Hi2 position includes a circuit design to fool this type of factory system into "seeing" a speaker connected to its output.
  • Crossover: The amp features switchable crossovers that can be set to low pass (LPF), high pass (HPF), or Full Range. You can adjust the cutoff frequency of the crossover from 32Hz to 320Hz using the rotary control. There are separate crossovers for the front and rear channels.

Connections: The Infinity Kappa K4 uses set screw terminals for the +12V power, ground, and speaker outputs. The screws can be tightened/loosened with a Phillips-head or flat-head screwdriver (not provided). The amp connections include:

  • Power/Ground: The +12V Power and Ground terminals will accept up to 4-gauge wire. It is recommended that you use 4 AWG power wire to the battery, with an in-line 60A fuse (or higher) installed no more than 18" from the battery terminal. A 4 AWG ground wire (minimum) is also recommended, and attached to a metal area close to the amplifier.
  • Remote Turn-On: The Remote turn on wire connects to the supplied plastic 2-pin Euro or Phoenix connector. The connector has tiny set screws to tighten the wire, and requires a precision screwdriver (2.4mm or 3/32"). The connector has "IN" and "OUT" terminals, allowing you to daisy chain the turn-on signal to another amplifier, if needed.
  • Speaker Outputs: The amp features screw terminals for connecting four speakers. There are markings on the terminals for bridging the amplifier.
  • Speaker-Level Input: The amp includes four bare wire-to-RCA adapters for connecting the amp to a factory radio or aftermarket head unit without preamp outputs. You should attach each speaker wire from the head unit to an adapter and plug the adapter's RCA plug into the amp.
  • Line-Level Inputs: The amplifier is equipped with two pairs of RCA inputs for connecting stereo RCA patch cables from the head unit to the amp.
  • Pre-Out: A third pair of RCA jacks is provided to output the audio signal to a second amplifier, if desired.

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Customer Q&A

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Crutchfield asked: Why did you buy this?
A
I choose this amplifier because it is powerful and has the smaller form factor to fit into my Honda Accord, underneath the front passenger's seat. [ Nicholas  Aug 12, 2019 ]
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I currently have Infinity Kappa Components in the front needing 100W RMS and kappa 3-ways in the back needing 75W RMS. This is a perfect fit being an Infinity and having the power needed to run the speakers. There were similar amps from other manufacturers, but I decided to stay within brand. [ Jeremy  Jun 26, 2018 ]
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I already bought a Kappa 600 from Crutchfield and was happy with it. Now the K4 driving two pairs of Kappa 62ix and the K600 driving a Kappa 1000 10 inch sub, my 2000 Blazer should sound as good as anything I have ever owned. [ Tom  May 10, 2018 ]
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I have the 6.5 Extreme and want the amp to match [ David  May 03, 2018 ]
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I wanted an amplifier that was rated compatible with the speakers I purchased and this one is highly recommended, durable and affordable [ Martin  Apr 21, 2018 ]
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power and quality, it's just that simple. [ WILLIAM B  Apr 14, 2018 ]
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Bang for my buck [ Joshua  Apr 10, 2018 ]
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On sale [ John  Apr 07, 2018 ]
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Quality. Deep sale. [ David  Apr 04, 2018 ]
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Bluetooth [ Anythony  Mar 31, 2018 ]
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Half price for good quality. Kappa has always delivered. I don't need the newest, just the best... [ Gram  Mar 17, 2018 ]
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because i have kappas in my car and the match is good for my system,plus they were priced great. [ M  Mar 05, 2018 ]
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I chose this amp based on the high quality of their speakers [ Daniel  Feb 05, 2018 ]
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Taylor instilled complete confidence in everything I bought today. I would have also bought a Infinity Kappa 60CSX 6.5" 2-Way Component Speaker System from him and AudioControl LC7i Black 6-Channel Line Output Converter with Bass Restoration, but I saw that Crutchfield sells these on Amazon for 20% cheaper than the Crutchfield website. Odd, but I can't turn a $75 savings so long as the revenue is still routing to crutchfield. [ Jeremy  Jan 09, 2018 ]
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I have an Infinity amp in my 2013 Mustang and it works well. Now I have a Kia Sorento with the base sound system. Kia Sorento's optional sound system has an Infinity amp with ClariFi that helps broaden the sound on compressed audio and that is why I wanted it as a replacement for my base stereo system.Better sound of course. I also replaced the base speakers and added a powered subwoofer. [ bernard  Jan 03, 2018 ]
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Replacing a 5 channel amp with a 4 channel and a mono amp. [ MARCCUS B  Jan 02, 2018 ]
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I like the kappa series speakers thought I try the amp. [ roy  Dec 22, 2017 ]
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100 watts rms for 4 channels. I have 4 speakers at 100 watt rms. Seems like a no brainer. It matches the size and look of the k600 which will feed my subs. Most sound forums that had someone setting up sound systems for PA or various facilities shot for 30 to 70 or 40 to 60 for High to Low speaker ratio. 30&40% mid & high. 60&70% for bass. While loud will be possible, my goal is what one forums user coined PMB = Pure Musical Bliss. [ Bradley  Dec 18, 2017 ]
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Great deal [ Michael  Oct 02, 2017 ]
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13 questions already asked

Q
what are the dimensions of the amp?
[ Nolan  Jun 16, 2018 ]
4 answers
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Amp is trash... burnt out within months of owning it....
[ joel  Jun 21, 2018 ]
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260 x 177 x 43mm 10-1/4" x 7" x 1-3/4" I can't link the pdf manual this came from but if you google Infinity Kappa K4 the first hit is the manufacturer's site.
[ Greg  Jun 20, 2018 ]
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10.25x7x1.75
[ eric  Jun 20, 2018 ]
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6 x 10 x 1.8 inches
[ Mark  Jun 20, 2018 ]
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Do you have to hook up the hard wired remote if you just want to connect Bluetooth to stream but don't plan on taking calls or using other features?
[ Susan  Mar 10, 2018 ]
2 answers
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Sorry Ms. Susan K.; My Infinity Kappa 1000 & Kappa 4 Amps, are still in boxes in my Bimmer's Trunk, I still need to buy one more K1000, K2, and another K4 from Crutchfield of course, so I havn't Really set a wire plan, but when I installed the module in the console of my Bimmer, there is a switch solely for BT. The Infinity Module is (null) right now, but I share the same druthers, BMW BT, Dension BT and now infinity. I hope all works out. V/R. EAM - Temecula, CA
[ Eduardo  Mar 25, 2018 ]
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No you dont. But to be honest its as simple as just pluging it into the amp and you can leave it rolled up next to amp or actually run it to your dash. Very simple. But you dont technically need it to use blue tooth. But this is not your best option if all your looking for is blue tooth. You would only buy this if you were going to put all 4 car speakers to the amp and the bluetooth is extra. My deck in truck is bluetooth so i dont actually bother using the amps BT. And the amps clarify technology makes a big difference in sound btw.
[ Ethan  Mar 25, 2018 ]
Q
If using this amp with Polk db6502 speakers, should the polk supplied crossovers still be used?
[ Randy  Mar 09, 2018 ]
4 answers
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Don't see why not. Odds are they were designed together will sound great together. Give them a little time. If you think they aren't what you like soundwise, then you might consider a change or upgrade.
[ Michael  Apr 02, 2018 ]
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I'm not 100 percent sure but I'll note that this amp give a ton of noise/whine. It works great but the engine noise is kind of annoying
[ Linda  Mar 25, 2018 ]
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Yes
[ jim  Mar 25, 2018 ]
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Yes use the same crossovers for you speakers does not have anything to do with amp.
[ Ethan  Mar 25, 2018 ]
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I'm looking to purchase this amp for 4 of my new alpine type s speakers. I also have a self amplified kenwood 8" under the seat sub (Ksc-11). Can I connect this to the amp just so I can have whatever I play on Bluetooth play out of the sub as well? Thank you
[ Josh  Feb 24, 2018 ]
3 answers
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yes it has a preamp out
[ eric  Mar 21, 2018 ]
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Yes, this amp basically acts like a head unit when you connect your music source to its Bluetooth.
[ Patrick  Mar 15, 2018 ]
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Josh, This amp is more than a way to connect bluetooth audio as it also has a hands free feature. Unless you still listen to radio or CDs toss the Kenwood connect all the speakers directly and hide the Mic and enjoy. But if you still have some emotional attachment to FM/XM or Cds well yes it can be connected to it either thru high power out or low power out very versatile. It must be the device connected directly to your speakers and it has a powered sub out connection. Hope this helps I bought it to eliminate the head unit and allow for a very clean uncluttered interior. I hid the controller under the lid of my armrest.
[ JONATHAN  Mar 14, 2018 ]
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If I only hook up 2 channels Will it be using power for those 2 channels only or will I using 4 channels worth of power?
[ stunami  Nov 12, 2017 ]
4 answers
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Each channel has its own independant maximum power output. So if it's 60 watts per channel rms then each channel will put out 60 watts. Each channel works separately.
[ James  Nov 23, 2017 ]
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You can bridge the left and rt channels for more power for those 2 channels
[ eric  Nov 18, 2017 ]
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It depends on how you hook them up. If you have them bridged at the amp, you can get full power to 2 speakers .
[ Robert  Nov 17, 2017 ]
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It depends on how you wire it. If you just use 2 channels wired as you would normally wire them, you will only have 2 channels worth of output. If you bridge the 4 channels into 2 channels, you usually get more than double the RMS power. For this amp, 2 bridged channels can put out 240W RMS, but you must make sure that your speakers have high enough impedance. This amp can push 2 ohm speakers in the standard configuration, but if you bridge the channels, you need to wire in 4 ohm speakers. The wiring configuration to bridge channels should be in the amps manual, but it is always very straight forward. Usually you would bridge the 2 front channels together, and the 2 rear together, by using, for example, the positive terminal of one of the front channels, and the negative of the other front channel. Just make sure to verify this in the manual so you don't break anything.
[ Louis  Nov 17, 2017 ]
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In addition to using this as a Bluetooth streaming device, I'd like to run my factory head unit through this amplifier so when i'm not listening to my iPhone, I can still listen to local radio stations. Is it possible to hook my factory head unit to this amplifier?
[ 2015 Chevy Trax  Oct 15, 2017 ]
3 answers
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It is good to ask questions but doing your own research is more powerful in terms of correct information. Crutchfield and Infinity are good about allowing anyone access to the owners manuals. You can hook a main unit with line inputs (RCA plugs) or high level inputs (speaker out on main unit). This amp comes with a small controller you can mount in a convenient location to change which input gets channeled through the amplifier.
[ ken  Oct 15, 2017 ]
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Yes, there are high level (speaker) inputs and if your radio is factory amped there are low level input rca adapters included as well. It is a very nice set up.
[ Rob  Oct 15, 2017 ]
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Yes line level inputs can be used...the amo comes wirh special rca hook ups.... this is a terrific amp n
[ eric  Oct 15, 2017 ]
Q
Can this amp be used as a stand alone Bluetooth player without the need of a head unit?
[ scott  Sep 24, 2017 ]
3 answers
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I am running it like this now. I hooked the speakers up directly to the amp and connected my phone with no issues.
[ Jacob  Sep 25, 2017 ]
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Yes, but in my opinion with head unit sounds better with use of a USB drive and you have more control over sound. Also depends on the quality of songs.
[ Jeremy  Sep 25, 2017 ]
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Yes it can. I have it in my Buick LaCrosse and I can have it k it up to the amp or my stock head unit. The amp has its way wn tuning also.
[ Patrick  Sep 24, 2017 ]
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How would I replace my factory amplifier in my 2017 Honda Crv Exl with this but leave the head unit?
[ Julie  Sep 02, 2017 ]
1 answer
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The K4 does feature "speaker level inputs" so, you can tap the factory amplified speaker leads to provide the audio signal. Because these are "high level" inputs, the factory amplifier will need to remain in order to provide the audio signal into the new amp. For additional assistance and personalized recommendations, feel free to contact us directly by phone or through our online chat service: https://www.crutchfield.com/support/ContactUs.aspx
[ Ryan  Sep 06, 2017 ]  Staff
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guessing if i was to use it with a dsp. this amp would take the dsp out of the equation if i am streaming via Bluetooth . so my sound imaging set up would do no good correct?
[ dopesrt  Aug 23, 2017 ]
1 answer
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You are correct. Sending audio into this amp via Bluetooth would bypass a DSP and not use any part of the audio adjustments you set up with it. There are ways to build a system so this doesn't happen. I recommend contacting an advisor on 1-800-324-9695 for a personal recommendation. My Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=101
[ Paul  Aug 28, 2017 ]  Staff
Q
Can Polk db652 speakers handle this amp?
[ Michael  Aug 05, 2017 ]
3 answers
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If the RMS wattage is right they should work fine. Infinity speakers run low amperage, therefore there amps are low amperage. You might need a more powerful amp if the polk speakers have a higher peak wattage
[ Kevin  Aug 05, 2017 ]
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I can't answer whether the db652's can handle it, but I have the Polk DB6502 component speakers and they perform beautifully with this amp. From a glance, the db652's have a similar response range...actually they look like the same speakers with a built in tweeter instead of the separate tweeter. I would say yes this is a good pairing just from the specs.
[ Chris  Aug 05, 2017 ]
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Definitely. I have the db652 and db6502 components hooked to this amp. Perfect fit.
[ Jared  Aug 05, 2017 ]
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How to connected to factory stereo 2015 toyota camry xle with jbl speaker ? I want buy Infinity Kappa K4 . Thanks
[ Thinh  Jul 04, 2017 ]
1 answer
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For 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 what you will need for an installation.
[ Kenny  Jul 06, 2017 ]  Staff
Q
can this be used just as an entertainment center for a vehicle? I have a tablet that I would like to use as a stereo instead of a head set.
[ Matt  Apr 17, 2017 ]
1 answer
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Sure! You can pair a Bluetooth streaming device (such as a tablet) to the Infinity amplifier and use that as the main audio source instead of an actual radio/head unit. If you would like to discuss in further detail, please feel free to contact an Advisor directly by phone (1-800-324-9695) or online chat. Hope that helps!
[ Larry  Apr 21, 2017 ]  Staff
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