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Kenwood KAC-M1824BT

Compact 4-channel amplifier with Bluetooth® connectivity — 45 watts RMS x 4 (Factory Refurbished)

11 Reviews | 4 questions - 12 answers


Our take on the Kenwood KAC-M1824BT

Kenwood's KAC-M1824BT 4-channel amplifier will pump up your car's audio system with 45 watts RMS per channel — that's more than twice the power of most car stereos. The super-compact KAC-M1824BT will add new clarity and impact to the basic sound system of almost any kind of vehicle on land or water, and it'll fit in a lot of places when space is tight. The amp uses plastic plugs that protect its power and speaker connections, and features a conformal coated circuit board that keeps out moisture and salt, so the party won't stop just because of a little wetness.

Power your music on land or sea

Kenwood's KAC-M1824BT 4-channel amplifier will pump up your car's audio system with 45 watts RMS per channel — that's more than twice the power of most car stereos. The super-compact KAC-M1824BT will add new clarity and impact to the basic sound system of almost any kind of vehicle on land or water, and it'll fit in a lot of places when space is tight. The amp uses plastic plugs that protect its power and speaker connections, and features a conformal coated circuit board that keeps out moisture and salt, so the party won't stop just because of a little wetness.

Play music wirelessly — no receiver necessary

If you store all your music on your phone or other portable device, you can use the KAC-M1824BT's wireless Bluetooth connection to play your tunes — a great feature if you don't have room to install a receiver. The wired remote controls the volume and track selection, and a USB port on the remote lets you recharge your device, so you won't miss a beat of the fun.

It also works with a receiver

The KAC- M1824BT comes with RCA connections so you can use it with an aftermarket receiver. It can handle speaker-level signals as well, so you can still get input from a radio without RCA outputs. The amp senses incoming high-level signals and turns itself on, eliminating the need to install a separate remote turn-on wire.

Bluetooth note: Use of this amplifier's Bluetooth features will depend upon your phone's Bluetooth capabilities. Learn more in our article explaining Bluetooth profiles.

Product Highlights:

  • compact 4-channel amplifier for car, motorcycle, and boat
  • 45 watts RMS x 4 at 4 or 2 ohms
  • 90 watts RMS x 2 bridged at 4 ohms (4-ohm stable in bridged mode)
  • CEA-2006 compliant
  • wireless Bluetooth connection via wired remote controller
    • Apt X technology improves Bluetooth sound quality
    • supports AAC files for iPhone® users
    • USB port on remote for charging your portable device
  • conformal-coated circuit board — suitable for marine applications
  • MOSFET power supply and Class D amp technology
More Features:
  • preamp and speaker-level inputs
  • preamp outputs
  • signal-sensing turn-on on speaker-level inputs eliminate need for a separate remote lead
  • 10-gauge power and ground leads recommended
  • fuse rating: 15A x 1
  • dimensions: 6-11/16"W x 1-13/16H x 3-7/8"D
  • warranty: 90 days
  • Our 60-day money-back guarantee

What's in the Box:

  • Refurbished Bluetooth 4-Channel amplifier with a 15A ATM mini-fuse installed
  • 59" Wiring harness (22-pin Molex plug on one end)
  • Remote control/Bluetooth control unit with attached 10.5' cable (12-pin Molex connector on one end)
  • Remote Unit mounting bracket
  • 4 Self-tapping screws (M4 x 16mm)
  • Two 13.5" Plastic wire ties
  • Dual-sided adhesive tape
  • Protective Cover for Controls (1 sheet)
  • Instruction Manual/Warranty Card

I was afraid when I got this that it might not be big enough and would be overpowered by my subs, but pushes my new rockford p-16's loud and clear...and the bluetooth works great too. alot of power for such a tiny amp

Iracema, Del Norte, Colorado


Kenwood KAC-M1824BT Reviews

Average Customer Review(s):

(11 Reviews)

Kenwood KAC-M1824BT

Crutchfield customer from Zanesfield, OH on 10/7/2018

Crutchfield Customer Review (What's this?)

Easy to hide, good sound, Bluetooth connection seems great so far.



Kenwood KAC-M1824BT

Crutchfield customer from Wyomissing, PA on 8/7/2018

Crutchfield Customer Review (What's this?)

Awesome, placed in 1974 Cadillac with Pioneer rear deck speakers and front tweeters, sounds great. No need to change stock system, makes cruising a whole new ride!



Great solution to my Bluetooth troubles

Brian from Chandler, AZ on 5/21/2018

Crutchfield Customer Review (What's this?)

I wanted a music solution for my backyard patio. It had to be Bluetooth to work off a dedicated 10 inch tablet. I wanted wired speakers because I tried Bluetooth speakers before and every time I wanted to listen to music I would have to turn them on then wait until they paired with each other, then to my tablet, which could sometimes be a couple of minutes. Not an ideal solution. So I stumbled on this amp, I used a 110 volt to 12 volt power converter, installed it in a modified cabinet on my patio and hooked up a pair of Polk atrium 6 speakers. Now I just walk outside, flip the power switch, it pairs immediately to my tablet and I'm listening to my tunes. I am very happy with this amp and it gives my 8 ohm speakers more sound than my neighbor's are happy with.

Pros: Easy set up, good wired remote, plenty of power

Cons: A wireless remote would be better.

Pretty good

Steven from Pine Bluff, AR on 1/7/2018

Crutchfield Customer Review (What's this?)

This amp works for the most part very well. I am powering a pair of 7.7 inch JL wake tower speakers with it, and they are pretty loud. When I first installed the amp I bridged it to 2 channels (which the directions say is ok at 4 ohms), and at high volumes it would cut out. I rewired my speakers to just two of the channels and now it works fine, just not quite as loud.

Pros: Low power consumption, small size, and the Bluetooth controller is very nice.

Cons: Cuts out in bridged mode, no adjustability.

Kenwood KAC-M1824BT

Crutchfield customer from High Point, NC on 10/29/2017

Crutchfield Customer Review (What's this?)

Great amp. Compact enough to fit under the glove compartment in my 2013 Wrangler. The Bluetooth function is a nice addition but it takes some getting use to since the buetooth function bypasses the headunit for volume (has to be controlled from phone or remote), balance and tone functions. I would definitely buy again, it really improved the sound volume and clarity in my jeep (installed with 6-1/2" Kicker speakers).



Kenwood KAC-M1824BT

Crutchfield customer from Flagstaff, AZ on 10/18/2017

Crutchfield Customer Review (What's this?)

I'm using this in an RV to link to a tablet which handles music, gps, backup camera etc... It's perfect, except the front to back fader is on the amp, not the control panel, so no control once the unit is mounted and hidden. The bluetooth link is awesome. When the tablet is turned on, within a few seconds, the link is up and music playing.



Great performance, great sound, great value

Diamond Dave from Portland, OR on 10/10/2017

Crutchfield Customer Review (What's this?)

This is a fantastic value and performance for a Bluetooth amplifier. If you need a small footprint, this is it. Definitely recommend. (NOTE: this is a wired remote to the amp) I recently purchased and installed this amplifier in my 1991 Miata, several days prior to a 2700mi roadtrip. My goals were to have a very small footprint amplifier with a Bluetooth connection so I can use my phone exclusively as the Source unit. I do have a stock radio, but am not utilizing it with this unit. Due to its small footprint, I was able to mount it under the dash on the passenger side of the car, without decreasing space in the passenger footwell. The sound volume and quality were perfect for my application. I was able to clearly hear the music at freeway speeds, while wearing earplugs, with the top down in my Miata (albeit, it was near max volume). The bluetooth connection was always strong and the pairing happens automatically and very quickly at each startup. The compact, wired, remote control is easy to use and works very well. Only two complaints with this amplifier: 1- the illumination is very bright and distracting at night time. 2- the USB port is direction on the amp, but I think it would be better positioned on the wired remote control

Pros: Small size Bluetooth performance

Cons: I'd like the USB port to be located on the wired remote control Illumination is too bright for me at nighttime

Compact and sounds great - zero hiss and I feel fine.

Crutchfield customer from Pembroke, MA on 10/6/2017

Crutchfield Customer Review (What's this?)

Just installed this in my 1971 Lincoln. Driving Alpine 4x6 up front and 5 1/4" i back. I bought scratch and dent and saved! ALong with speakers, I'm all in at a great price! Anyway. Sounds great. Key for me was keeping my vehicle as 100% stock as possible. So this AMP is very small and tucked right inside the dash, above the glovebox. Still room for my gloves. The remote has it's own volume and play controls, but I don't use them. i set vol at 50%, put the remote in the glove box and now every time I get in my car and turn the key - my iPhone syncs immediately and I can play Amazon Music, iTunes, Spotify, Pandora etc all without plugging in anything or even removing the iPhone from my pocket. SWEEEEET

Pros: Small, great price

Cons: I bought scratch and dent - first one they shipped me was defective, but good ol' Crutchfield cross shipped me another and all set now

dynamite comes in small packages!

Iracema from Del Norte, Colorado on 3/20/2017

Crutchfield Customer Review (What's this?)

I was afraid when I got this that it might not be big enough and would be overpowered by my subs, but pushes my new rockford p-16's loud and clear...and the bluetooth works great too. alot of power for such a tiny amp



Kenwood Bluetooth Amplifier

Andrew from Tamuning, Guam on 11/20/2016

Crutchfield Customer Review (What's this?)

Installed in a 2007 Nissan Quest Van with oem integrated (non-removable) system.I could not simply replace the stock radio/cd/dvd player, but I wanted to be able to stream music from my phone. This bluetooth amplifier fit the bill. I was able to stream high quality music using the aptx codec. I still use the stock system through the speaker line outputs to the amp and drive the speakers with the new amp. I'm electronically inclined so it took just under 3 hours to install this amp and new speakers. I chose this amplifier for the increased output and installed high quality speakers. The difference is amazing! I should have upgraded my sound system years ago.

Pros: small unit size, line level and speaker level input, wired remote with 3m cord, 4x45w RMS bridgeable output.

Cons: Minimalist instructions included. Tough time finding wiring diagrams for stock radio. Full range output to speakers only - no low- or high-pass filters.

Great little amp

Joe from Greenwood, IN on 11/8/2016

This is a great little amp. I am using it to add BT connectivity in a 20 year old BMW 740iL that would have been a nightmare to replace the factory headunit in. The remote fits perfectly in the ashtray area, though it doesn't allow the cover to close. I wired it in to the factory wiring for power and speakers, and as such, I have to have the factory headunit on, but I'm OK with that. It sound great, and does drive Polk 5.25" coaxials (for now) in the front door, and the factory rear door woofers. There is NO crossover on this amp, so it runs wide open. Setup was easy, and the included manual told me what I needed to know. I do use BT as the source, and the passthrough still works even without the RCA inputs being used. This was a good thing to have. The only thing that I noted was that the pink wire which powers the lights in the remote was not secure and can not readily be made so, in the connector at the amp. I'm not overly concerned about it, and I made a quick little fix for it, and it's been fine ever since. Even being a Class D amp, it will still get pretty warm when pushed. We will see what happens long term with it. Even with the system in the car not fully setup and tuned, it will still get ear splittingly loud. I use a tablet as my source, and it's not been over half volume. I'm floored by that.

Pros: Clean sound Easy setup Small form factor Good instructions

Cons: No HP/LP filter Gets warm Loose wire from the factory (pink wire for remote lights)


Hands-on research

Product Research



Compact Amplifier: The Kenwood KAC-M1824BT is a compact Class D 4-channel amplifier with Bluetooth wireless technology. The amp features a conformal coating on the circuit board to protect it from moisture. This allows you to use the amp for motorcycles, marine applications, or on All-Terrain Vehicles (ATVs). The KAC-M1824BT delivers 45 watts RMS x 4 channels at 4 or 2 ohms. It also gives you 90 watts RMS x 2 at 4 ohms bridged. The amp operates at full frequency range, and is not designed to power subwoofers.

Bluetooth: The built-in Bluetooth wireless technology lets you use your smartphone or Bluetooth digital music player as your primary listening source. This makes the amp ideal for putting a sound system in a classic car, ATV, motorcycle, or other motorized vehicle. The amp comes with a wired controller for raising or lowering the volume and changing tracks. The attached 10.5' cable allows you to place the compact amp in a remote location. The KAC-M1824BT is compatible with Bluetooth Ver.3.0 + EDR, and supports SBC, AAC, and aptX for better sound quality.

Remote: The supplied Remote Control unit's Source button lets you pair the Bluetooth device, as well as switch between sources (Bluetooth or RCA/Speaker Input). Other controls include Play/Pause, Backward Skip/Fast Backward, Forward Skip/Fast Forward, and Volume Up/Volume Down. The remote can be surface mounted using the supplied double-sided tape, or flush-mounted in the included bracket. It also has a 1/4"-20 thread (same as a camera tripod thread) that allows you to attach the remote to an optional bar mount kit.

Protection Circuitry: The amplifier features protection circuitry for thermal overload, DC offset, and short circuits. The amp stops operating when it goes into protection mode. (There are no LED indicators.)

Signal-sensing Turn-on: When the amplifier is connected to a factory head unit, or an aftermarket unit without preamp outputs, you can splice the head unit's speaker wires to a speaker-to-male RCA adapter. In this case, the amplifier's Signal-sensing Turn-on feature will turn on the amp when a signal is detected on the input. This eliminates the need to connect a turn-on lead to the amp's Power Control (blue) wire.

Mounting: The KAC-M1824BT can be mounted onto an installation board (5/8" thick or more) using the supplied M4 x 16mm self-tapping screws. Two 13.5" plastic wire ties are included for securing the amplifier to a 2x4 board or other narrow item.


Power Connections: The power, ground, power control, and speaker output wires are included in the supplied 6' wiring harness. The 16-gauge yellow power wire can be spliced into the continuous power wire for the head unit. It is not necessary to run the power wire directly to the battery. The ground wire should be run to the vehicle's chassis.

Power Control: The Power Control (blue) wire should be connected to the head unit's remote turn-on lead when an aftermarket unit is used. This wire does not need to be connected if you're using speaker level inputs. The Signal-sensing Turn-on feature will turn on the amplifier when an input signal is detected.

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. If using a factory head unit, or a unit without preamp outputs, you can splice the speaker wires to an RCA plug, maintaining the same polarity.

Line-Level Outputs: In addition to the line inputs, the KAC-M1824BT has one pair of RCA line outputs. This allows you to feed the input signal to another amplifier, if desired.

Speaker Outputs: The included harness has eight 20-gauge wires for connecting your speakers to the amp. You can connect the eight wires to the 4 speakers in a Front Left & Right and Rear Left & Right configuration. By bridging the amplifier, you can get higher power output to two 4-ohm speakers. The amp's Output Mode switch should be placed in the appropriate position depending upon how the speakers are wired: Stereo 4-channel or Bridged 2-channel. The wiring diagram for both configurations can be found in the instruction sheet.

USB Charging Port: A Type A USB port is provided on the amplifier for charging an iPod, iPhone, or Android device. For charging your device, you should use the cable included with your device or the optional KCA-iP102 (30-pin), KCA-iP103 (Lightning), or Micro USB 2.0 (Android) charging cable.

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.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

it had bluetooth, and a remote as well. [ Christopher  Sep 10, 2018 ]
PRice quality using on my cruiser [ Robert  Jul 21, 2018 ]
Mounting it in the trunk of my 1990 Nissan Skyline GT-R so it stays proper with no radio in the inside of the car [ Eric  Dec 20, 2017 ]
pricing and brand [ Sherry  Mar 17, 2017 ]

4 questions already asked

You have to use the audio equalizer on your phone, if it doesn't have one you can download an app. You can use this amp with a head unit for better quality sound equalization, but then you'd have to use the Bluetooth input of your head unit and just unplug the remote. [ STEVEN  Jan 27, 2019 ]
I don't think this has eq function. The amp doesn't have any fine tuning filters..only gain volumes. And i don't think you can hook an eq up to is just a basic bluetooth receiver/amp. I'm using it on my will power 4 speakers. I use Pandora from my phone or maybe your bluetooth device will have sound settings so you can tune to your preference. [ joseph  Jan 27, 2019 ]
Good question! So I hooked it up to eq on my bench, and the blue tooth is independent of the eq. The Bluetooth can not be be eqilized with separate eq. It is a separate signal. The Bluetooth can only be equalized via the device's eq( iPhone etc.) [ RAY  Jan 26, 2019 ]
Yes, the RCA output will transfer the audio signal from either the Bluetooth or RCA input to an external amp/subwoofer in your system. For more details or to discuss further, please contact an Advisor directly by phone (888.955.6000) or online chat. Thanks! [ Larry  May 03, 2018 ]  Staff
Yes. That round button that says "SRC" lights up RED if you are using a device that connects with RCA cables and lights up BLUE if you are using a device to play music through a bluetooth connection. [ david  Apr 12, 2018 ]
Yes, as long as you wire the receiver up correctly, my reciever had rca outputs if I remember correctly . Then all you have to do when you want to use reciever is press the source button (lights red for reciever and blue for Bluetooth) this was a perfect amp for my pontoon boat, also have a bass tube. I hope I answered what you were asking. [ MANNY  Apr 12, 2018 ]
yes..when the remote is red it's on the reciever...when it's blue it is bluetooth....we sure like ours [ Iracema  Apr 12, 2018 ]
I am only using the unit for bluetooth and do not have a separate receiver. Sorry I couldn't answer your question. [ Richard  Apr 12, 2018 ]
There is a source switch. You choose between bluetooth connection or the receiver output. [ Andrew  Apr 12, 2018 ]
The 'SRC' button in the middle of the wired remote controller allows you switch between the RCA inputs on the amplifier and the internal bluetooth receiver. If you connect your receiver to the RCA inputs you can switch between your receiver and bluetooth input. [ Bryan  Apr 12, 2018 ]
Yes, it can be used on eithet Bluetooth or as a 4ch amplifier.. it's got source select. [ mike  Apr 12, 2018 ]