SK-M4004D | 400 Watt 4-Channel Car Amplifier

  • Skar Audio SK-M4004D 400 Watt Class D 4-Channel Car Amplifier - Front View

SK-M4004D | 400 Watt 4-Channel Car Amplifier

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The Skar Audio SK-M4004D full range class D four channel amplifier is part of the new mini amplifier series product lineup from Skar Audio. The SK-M4004D was engineered to be compact, but provide the power and reliability expected out of larger amplifiers. Featuring a high speed MOSFET power supply, and an efficient Class D design, this amplifier is powerful, reliable, and extremely versatile. The SK-M4004D makes for a great amplifier in applications where space is limited but power cannot be sacrificed. In addition, this four channel amplifier features high level input connections for those installations that lack an RCA connection. In addition to the high level inputs, this amplifier also utilizes an adapter harness for the speaker outputs allowing for an easier installation.


*Skar Audio always recommends professional installation for all of our products.*


*Never mount amplifiers directly on the enclosure*



  • Compact "Mini" Class D Full-Range Four Channel Car Amplifier
  • The compact design of this amplifier series allows for maximum versatility
  • RMS Power @ 2 Ohms: 140 Watts x 4 Channels (14.4v)
  • RMS Power @ 4 Ohms: 100 Watts x 4 Channels (14.4v)
  • RMS Power @ 4 Ohms (Bridged): 270 Watts x 2 Channels (14.4v)
  • Frequency Response: 10Hz - 40kHz
  • Working Voltage: 8.5V-16V
  • Signal-to-Noise Ratio (Sensitivity): 85dB
  • Efficiency @ 4 Ohms: 86%
  • Damping Factor: 100<
  • Low Level Input (Gain): 8V - 0.2mV
  • Hi-Level Input Connections: Yes
  • Speaker Output Adapter Connection: Yes
  • Crossover Control: HPF / Full-Range / LPF
  • 4-Way Protection Circuitry Built-in (Thermal, Voltage, Speaker, DC)
  • LED Power & Protection Indicators
  • Fuse Rating: 40 Amps
  • 8 Gauge Power and Ground Input Terminals
  • Dimensions: 7.9in x 4.6in x 1.7in (L x W x H)

Channel 1/2 Crossover

  • High-Pass Filter / Full-Range / Low-Pass Filter
  • Variable Crossover Frequency Range: 50Hz - 500Hz

Channel 3/4 Crossover

  • High-Pass Filter / Full-Range / Low-Pass Filter
  • Variable Crossover Frequency Range: 50Hz - 500Hz

Click Here to Download the SK-M Amplifier Manual

Customer Reviews

Based on 8 reviews
Great product!

Very clear highs and miss, wired down to 2ohms. Doesn't overheat!


What a bang for my buck I mean these amps truly Supply the power you need at the time you need it. I have one on 4 6.5 skar component speakers and the other on 2 4 inch skar tx4s and 1/8 in 125 watt RMS loudspeaker bridged and I say loud and clear ain't the word. I highly recommend this app for anyone that wants clear power Precision.

Good little sucker

Working very good. TOO GOOD. I have this amp powering 2 sets VXI65 components with upgraded st01 tweeters and I have a rp1500 pushing 2 VVX12 V3s at 1 ohm. Ive got a 2008 gmc sierra with a 160a alternator that is actually weak and needs upgrading. I've got both amps turned way down to prevent too much voltage drop which is cutting out my 4channel. Overall great amps just need to ground the amp better which may be a culprit as well as upgrade to a mechman 240a

Excellent 4 channel

The quality of this amp is unbelievable and its really convenient how small it is! I highly recommend this amp

Best class D small footprint amp available. Huge sound in a little package.

I replaced the stock Infinity amp in my 2000 Jeep Grand Cherokee with this little Gem.
It's powering a total of 4 of the SK 6x9 and the VX200-ST tweeters. Super clear sound and plenty loud enough to keep up with the 2 Evl 12's running on 2 RP2K. I love Skar products and the customer service. Definitely can't beat the prices either. SKAR for the win. Anyone looking for a Class D 400.4 4 channel amp can't go wrong with this baby. Best 4 chanel amp I've ever had. I have the 3rd &4th channel running at 4 ohm and the 2nd & 3rd chanel at 2ohm.