Ultra Compact

SK-M Series

Product Info

General Specifications

Channel 1/2 Crossovers

Channel 3/4 Crossovers

Channel 5

Real World Amplifier Dyno Test Results

User Manual

SK-M4004D | 400 Watt 4-Channel Car Amplifier

The Skar Audio SK-M4004D is an ultra compact, 4-channel, class D car amplifier. This amplifier was designed for maximum efficiency and power output, allowing you to power all of your aftermarket speakers while hiding your amplifier.

SK-M4004D | 400 Watt Class D 4-Channel Car Amplifier

SK-M4004D

It sounds good with my speakers, and it fits pretty well in my Harley front fairing.

Andrew

2015 Harley street glide 

This amp plays very clean. I have been playing it through my 4-door Skar Audio speakers, of course.

SKAR at it’s best

Richard

Perfect 

I just installed this little amp in my 2022 Silverado. I was very skeptical about buying this amp but needed something small due to space restrictions. It's pushing JL C3 650's in the front and C1's in the rear. It definitely did not disappoint. My only complaint is that there are no real heat sinks to dissipate the heat. It gets warm real fast when run kinda hard. Other than that, for the price, it's a good piece of equipment.

Thomas

Power house

It is super small, but still lets the door speakers scream!

Mick

Tiny but loud

James

Skar audio 

Amps work great and if you do have a problem skar will take care of you that's a fact

David Davis

Doin it Nasty style

Amp is small and compact but sounds crisp clear

Alex Montero

Sounds great

Marquis Adams

Perfect

You will not believe the power of this little thing. It's the size of a envelope with the power of a shoe box lol.... and it came in on a sunday love it so much THANKS AGAIN SKAR AUDIO

Bee Vue

Amazing

Great amp. Great size, Great sound from my speakers.

Matthew Norquist

Amplified

Purchased to replace a problematic JBL amp. This amp is half the size of that one and puts out a little more power. Im running 4 door speakers at 2 ohms each and even at full tilt for extended play time the amp just barely gets warm, not hot at all. I would prefer to see 4 gauge power inputs but the 8 gauge seems to get the job done.

Daniel Lawson

Great amp in a small package.

My wife bought me this amp for my birthday.  At first I didn't care for the speaker output pigtail (would prefer screw terminals), but during installation it helped to keep everything nice and tidy on my board.  Seems to deliver plenty of clean power to my components and gets plenty loud for what I want.  I love the small footprint!

Perfect size and output for my needs

I only can complain about the inputs. I wish the inputs weren't pre assembled on the clip so I could use my own wiring

Jose 

Good customer service

I bought 2 of these during the sale event and installed one in my daily F-150 Super Crew, and just finished the second one today in my daughters Mustang. There are rumors of heating issues but haven't experienced any yet. These little amp sound great. I'm very impressed with their small size and great sound quality as well as the level. I definitely recommend this amp especially when a small size is needed.

B-ri

Great Little Amp

Great definitely does the job love the size very compact and just looks perfect in my car

Justin Long

So-m4004D 4 channel amp

Mark McCune

Skar build

Its a decent amp but the first thing I noticed is that the gain pots are backward. They go from 0.2 to 8v and you would think that 8v is Max but that is not the case (at lest on mine?). Make sure you tune these amps with a sine wave tone generator, a multimeter, oscope, or an SMD DD1 to make sure you aren't clipping your signal.
For the price though its a decent amp and it fits basically anywhere. Good value for the money.

Skar, please consider changing the printed gain indicators to Min-Max to avoid confusion or at least ensure the pots attenuate in the proper direction. This was very confusing initially.

Photo: SK-M4004D is mounted on the right.

Seth F

Decent Compact 4 channel

I was a little worried that these amps would be a little week. Installed 2 400w and one 500w today. Very happy and surprised. On top of that they shipped super super fast. Awsome product