Compact 4-channel amplifier — 45 watts RMS x 4 (New stock)
Item #: 113KAM1804
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Item #: 113KAM1804
Your price: $149.99 Earn up to 150 Rewards points
Kenwood's KAC-M1804 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-M1804 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 covers to protect its 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.
The KAC-M1804 comes with an RCA cable for connecting to an aftermarket receiver, but it can handle speaker-level signals as well, so you can still get input from a radio without RCA outputs (Crutchfield recommends using the Kicker KISL adapter to allow you to keep the RCA leads from your amplifier). The amp senses incoming high-level signals and turns itself on, eliminating the need to install a separate remote turn-on wire.
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.
Works as advertised, good little amp with no frills
Pros: Small Size
Cons: No ability to make adjustments to sound on the amp. Small enough to put in tight spaces but heat is still your works enemy.
I bought this with the Kenwood Excelon DNX692. Using the stock speakers in my Rav4 the sound is better than ever before. If you do not have amplified speakers in your car and are adding a double din head unit I recommend adding this guy to your system. I have not cranked it all the way up because the sound is really clear at a level that I can stand as it is but if I need more I will upgrade the speakers as well.
Pros: Easy to install with Metra 70-1761 Receiver Wiring Harness for the Rav4 by wiring directly into the direct fit plug. I did solder the connections for the harness and shrink wrap them but it was a fairly easy install. No splicing the car wires. If I want to sell my car all I have to do is unplug everything and plug back in the stock radio. I am taking this set up along with me in my next car. I do love Kenwood products for the high quality.
Cons: No direct fit wiring but I don't think you can get that anywhere. I was able to make my own with Metra 70-1761 Receiver Wiring Harness that I purchased with it solely for that reason.
Does exactly what it says. My first 4 channel amp install so took some time to figure out how to wire and ideal placement in my car. Crutchfield advisors were great in helping out with this.
Pros: Low voltage draw, lots of installation options and flexibility.
Cons: None so far.
Great little amp that has plenty of punch for my (4) 6 x 9's. Installed easily in about an hour. Highly recommend if you want plenty of power for the average car...my ears were ringing when turned up and very clean.
Pros: Small, easy to install
Cons: Included hookup wires were pretty cheap. I recommend getting an aftermarket Amp install kit with better quality wiring.
small is right! it's only running 4 motorcycle speakers and ran for about 30 min before it started cutting out. This is at half volume and I installed 2 cooling fans to run across it. I wouldn't but this amp.
Cons: over heats and or cuts out in 30 min
This is a great little amp. Little is the key word there. I fit this little thing behind the dash above the head unit in my Expedition. TONS better than my stock stereo. But I also replaced the head unit with a Kenwood DDX672BH. So I'm sure that helps too. The speakers were the same Kicker 6x8 components that I had installed a couple of months before. 45W is only 45W so, keep that in mind. But if you need more power buy something else. But for very decent power in a tiny package, this is great.
Pros: Size Sound quality
Cons: None really
I installed it in a marine application and this little amp really pumps out some decibels! The best thing about it was the size, easily fit behind the gauge cluster. The wiring harness has about 6' of wire and a couple zip ties included.
Pros: Compact size, 400WATTS!!!
Great sound. Install was a little complicated due to the harness. I wish that I had gone with a more standard setup.
The Kenwood amp provides clean power to my boat stereo system. Great price and quality make this Kenwood purchase a great value!
Sound quality is awesome. I have this paired with a Pioneer AVH-X2600BT and driving two sets of Kicker speakers in my 1988 Toyota MR2, and the sound is phenomenally crisp. The highs are super clear, and the mids are delivered very cleanly. And this thing is small. No, not that small...smaller.. No, not that small either... smaller... This thing will fit just about anywhere. It's about the size of a long Kleenex box, but less than half the height.
Very happy with this to drive my speakers. Works flawlessly, and with so little space in the MR2, it's wonderful to be able to fit both amps under one seat because of how compact this thing is. Amazing that it can be that small and have no perceivable detriment to sound quality.
Please bear in mind that this does not have a standard screw type wire connection. It is a proprietary harness similar to what you would find on a head unit, except that the wires coming out are 16 AWG, and a 12 AWG (I believe) for the power wire. This shouldn't be too much of an issue as the power draw is very low, so there is no need for large wires.
Pros: ULTRA Compact Size Sound Delivery Ease of Wiring Low Power Consumption Does not need direct wiring to battery
Easy to install-very compact. Produces great sound
Pros: Install was very easy, very compact and water proof.
I bought this amp to boost the sound on my pontoon boat and am very pleased. Sound quality is fantastic. I can run 20 mph and hear my radio now over the water and wind noise. Great amp for the money.
Pros: Good value
|RMS Power Output (Watts x Channels)||
45 x 4
|Peak Power Output (Watts x Channels)||---|
|Power at 2 Ohms (Watts x Channels)||N/A|
|Bridged Power (Watts x Channels)||N/A|
|Minimum Impedance Bridged||N/A|
|Minimum Impedance Unbridged||4|
|Best Frequency Response||20-20000 Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||74 dB|
|Low-Pass Crossover Frequency||N/A|
|Low-Pass Slope (dB/octave)||N/A|
|High-Pass Crossover Frequency||N/A|
|High-Pass Slope (dB/octave)||N/A|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||RCA/Bare wire|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Compact Amplifier: The Kenwood KAC-M1804 compact Class D 4-channel amplifier is designed to boost the output and clarity of your car stereo. The amp features a conformal coating on the circuit board to protect it from moisture. This allows you to use the amp for marine applications, or on All-Terrain Vehicles (ATVs). The KAC-M1804 delivers 45 watts RMS x 4 channels at 4 ohms. It cannot be bridged or operated at impedances less than 4 ohms.
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 cut off the amp's RCA input connectors and splice the head unit's speaker wires to the input wires. 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.
No Controls or Crossovers: The KAC-M1804 does not have built-in crossovers or controls. If you are connecting the amp to small speakers, it is recommended that you use the crossovers built into the connected head unit, or use bass blockers on the speaker outputs.
Amp Wiring: The Kenwood KAC-M1804 is equipped with a 22-pin DC connector on the amplifier. The included 5' DC harness, which plugs into the connector, has wires for +12V battery power, ground, power control (turn-on lead), and four speakers.
Power/Ground: The +12V Power and Ground wires are 16 AWG wires. The power wire can be connected to the car's fuse box or directly to the battery. The amp is protected by a 15A ATM mini blade fuse. If wiring directly to the battery, you can use a 10 AWG wire with an in-line 15A fuse installed no more than 18" from the battery terminal. The ground wire should be attached to a metal area close to the amplifier.
Power Control: The blue Power Control 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 pair of RCA inputs on 7-1/2" pigtails for connecting stereo RCA patch cables from the head unit to the amp. Two 38" stereo RCA patch cables are included. If using a factory head unit, or a unit without preamp outputs, the RCA inputs will also accept a speaker level signal. The RCA jacks can be cut off, and speaker wire spliced with the existing cable, but adding a speaker level to RCA adapter is much easier (sold separately).
Speaker Outputs: The included DC harness has eight wires for connecting four speakers to the amp: Front left (white + white/black), Front right (gray + gray/black), Rear left (green + green/black), and Rear right (purple + purple/black). The amp is not capable of bridging or connecting to speakers with impedances less than 4 ohms.
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if it'll fit, it is not advertised as waterproof, only moisture proof. not sure if there would be any interference from being so close together [ jay Dec 21, 2015 ]
Yes you can, however I didn't find it to be powerful enough. I've built a bunch of bike systems and tried this one. I was very impressed in my garage but then to get it loud enough on the bike over the sound of the motor. I also bought from Crutchfield the Alpine KTP 445U amp and IT CRANKS! I have mounted them in fairings and the power it's amazing! Your best bet is to pair it with some Polk DB speakers. Hope this helps. [ DENNIS M Dec 21, 2015 ]
This model does require a 4 channel signal when using the RCA pre-amp inputs but this is an easy fix; you can use RCA Y-adapters to create the additional two connections from the single pair of outputs on your stereo: http://www.crutchfield.com/p_120RCAY1/T-Spec-RCA-Y1-Y-Adapter.html You won't be able to fade between the front & rear pair from the stereo but you will be able to provide audio to all four channels of the Kenwood. I hope that helps! [ Ryan Nov 20, 2015 ] Staff
You need to put it somewhere that will get some air circulation or where the amp can freely radiate its's heat, like just under the passenger side dash on the firewall, just above the top of the carpet if there is room, but not in direct line with the heater air. Mount it so the amp can freely radiate its heat. I would not bury it behind the dash. Under a seat is the alternative. [ JOHN Jun 29, 2015 ]
I have it in my boat and it does run hot. I need to add some type of cooling system. I'm thinking of adding a fan or some type of ventilation to the current compartment. I think I would have this issue with any system. Not just Kenwood. Sounds great but just gets hot after a little while. Good Luck. [ James Mar 07, 2015 ]
Have not noticed it getting hot. Should be fine for an in dash application. [ Timothy Mar 06, 2015 ]
This will run cool but you WILL be dissapointed with the power. It is in your best interest to get the alpine KTP-445U. Same price, from Crutchfield AND it cranks!!!!!!!!! I own and used both. The ken wood is most sub par, I hate to say. [ DENNIS M Mar 06, 2015 ]
I have a 2013 HD Street Glide. Will this amp plug easily into the factory radio or will I need to have it professionally installed? [ Brad Jul 23, 2014 ]
The input level is set automatically. There are no controls. That said, I am very happy with the unit. It takes up very little space and the sound quality is excellent. [ Thomas Jul 19, 2014 ]
I forwarded your question to an Advisor and they responded with the following: It's perfectly fine to slightly overpower your front speakers, so the 45 watts will work in this application. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy Jul 11, 2014 ] Staff