High-level performance is what MTX amplifiers are all about! The sound pros at MTX subject each Thunder series amp to rigorous bench testing before they'll let it ship, and they pack each model full of features designed with you, the music lover and audio enthusiast, in mind.

The Thunder801D mono subwoofer amp drives the hungriest 4-ohm sub with 400 watts RMS of Class D power. Hook up a two-ohm load, and the output doubles to 800 watts! MTX lets you harness this brute force with a variable low-pass crossover (40-200 Hz, 24 dB/octave) and the legendary ThunderEQ bass boost (0-18 dB at 40 Hz).

Heavy-duty, nickel-plated terminal block connectors efficiently transfer current into the amp. Inside, high-powered transformers and MOSFET-fueled Class D technology deliver massive power, while Intelligent Surface Mount Design isolates various amp sections for greater stability and lower noise levels. The result? Deep, pounding bass that you can crank to the max!

Product Highlights:

  • 400 watts x 1 at 4 ohms
  • 800 watts x 1 at 2 ohms
  • requires 4-gauge power and ground leads — wiring and hardware not included with amplifier
  • Adaptive Class D Technology
  • variable 40-200 Hz low-pass crossover, 24 dB/octave
  • preamp outputs
  • PWM MOSFET switching power supply
  • gain control
  • Thunder EQ bass boost (0-18 dB at 40 Hz)
  • speaker-level inputs with SmartEngage (turns on the amp when it detects signal from the receiver, eliminating the need for a turn-on lead)
  • 11-5/8"W x 2-1/4"H x 9-13/16"D
  • 1-year warranty

MTX Thunder801D Reviews

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MTX Thunder801D

Written By dusty, star city, ar on Wednesday, April 13, 2005

this mtx 801d amp is one great amp. i have it pushing 2, 12 in. infinity kappa perfect vq subs and it pushes them without a problem. the amp stays cool even after long hours of hard hitting bass.

Mighty mouse!

Written By Michael, Mckinney, TX on Sunday, February 20, 2005

This little amp has a fairly small footprint, but delivers stout power! I have it hooked up to one Audiobahn DUB1200 Sub (750W RMS) and @ 2 ohms, the MTX801D delivers about 900 to 950 watts of power RMS. The power is very adequate, and allows me to keep the gain down to around 60% of max.

The external bass controller is a must for remote mounting locations. The extra little features are great, the compression circuit, and all the extra design features built to improve signal to noise ratios.

This is one solid amp, that is built for the long run. It survived a long 8 hour road trip (one way) with absolutely no heat or performance issues. Again, this is one 5 star product!

Hands-on research

What's in the box?

Download owner's manual

  • 1 Mono-block amplifier
  • Speaker-level input harness
  • Owner's manual
  • Amplifier Input/Output Connections sheet
  • Amplifier Performance Certificate
  • MTX Audio sticker
  • Mono Amplifier Impedance Requirement sheet (attached to inside packaging)

Product Research

Inputs and Outputs
Wiring Recommendation


Patented PWM MOSFET Switching Power Supply:  This type of power supply is used for maximum power output and protection.

Adaptive Class D Technology: While typical Class D amps tend to generate high frequency energy that must be filtered to prevent harmonic interference in the FM radio frequency range, Adaptive Class D Technology directs the amp's switching energy away from FM radio ranges as the amp's load and output increases. This improves the amp's overall signal-to-noise ratio and eliminates interference generated by more common Class D amps.

Pure N-Channel Design: The pure N-channel design is more linear than typical N-Channel designs, so the speaker you connect to the amplifier will be better controlled. The signal travels through fewer parts so the signal-to-noise ratio is enhanced, the power rating is better, and the amp runs louder, longer.

Low Impedance, High Power Transformers: These provide more power and produce less heat.

Compression Circuit: The amplifier's compression circuit prevents the amplifier from clipping, even at high volume levels. The circuit protects the speakers against the potential damage that can occur during dynamic musical passages. The circuit can be turned on or off, however damage to speakers may occur when the circuit is in the "off" position.

Smart-Engage: If you're planning to keep your factory radio and use the amp's speaker level inputs, Smart-Engage senses the source voltage from the factory radio, meaning you won't have to run a separate turn-on lead and won't necessarily have to remove the factory radio during installation.

Real-time Computerized Protection Circuit: The protection circuit makes sure you amp is operating within safe parameters for maximum power and protection.

Acoustically Seamless Turn-on/Turn-off: A circuit that prevents turn-on/turn-off "thump" is included to eliminate turn-on/off noise.

Iso-Feet: Four rubber Iso-Feet are attached to the amplifier. The rubber feet let you mount the amp securely, while preventing the mounting screws from coming into contact with the amp's chassis.

RCA Outputs: In addition to the set of preamp inputs, there is a set of buffered RCA preamp outputs. The left and right outputs are summed, providing a mono signal, plus the signal is low-pass only, filtered by the amplifier's built-in crossover. The outputs allow you to daisy-chain one bass amplifier to another. Also, the RCA output jacks allow for multiple bass amplifiers to be level controlled using one EBC (sold separately).

EBC (Electronic Bass Control) 2: This amplifier includes an Electronic Bass Control Port (RJ-11 jack) that will accept the cable from an optional EBC. When an EBC is connected, you can adjust the bass level from the driver's seat to overcome noise and other interference. With EBC 2 multiple compatible amps can be controlled.

Intelligent Surface Mount Technology: Features substantially shorter internal and external lead lengths, reducing stray capacitance and inductance, which results in cleaner and more accurate musical reproduction with less noise interference.

Thunder EQ: Thunder EQ is a continuously variable Bass Boost (0-18 dB) centered at 40 Hz. 

Crossover: This amplifier is equipped with a 24dB/octave, low-pass crossover that is always active. There is a crossover frequency control, continuously variable from 40 Hz to 200 Hz, that allows you to dial in the low-pass cut-off frequency of your choice. Note: The built-in crossover also filters the amplifier's line output.

Terminals: The terminals are nickel-plated, heavy-duty screw terminal connectors.

Performance Certificate: MTX tests each amplifier, and the technician records the "actual" power output on the Certified Performance Certificate included with each amp. The amp must meet or exceed the rated specification in order to leave the factory.


Dynamic Power Measured at 14.4 Volts DC:
  • 400 Watts x 1 into a 4 Ohm load
  • 800 Watts x 1 into a 2 Ohm load

RMS Power Measured at 12.5 Volts DC:

  • 250 Watts x 1 into a 4 Ohm load
  • 500 Watts x 1 into a 2 Ohm load

Inputs and Outputs

Left Side of Amplifier:

  • Line In: RCA stereo jacks
  • Line Out: RCA stereo jacks
  • EBC Port: a telephone-style (RJ-11) jack for an optional EBC (Electronic Bass Control) 
  • Speaker Level Input: a 4-pin input for use with the included speaker-level input harness

Right Side of Amplifier:

  • +BATT: (power): screw terminal (terminal is 0.54" wide)
  • REM (remote turn-on): (terminal is 0.34" wide) 
  • GND (ground): screw terminal (terminal is 0.54" wide)
  • Speaker Terminals: there are two sets of terminals (labeled Speaker 1 and Speaker 2), but they are wired internally in parallel and they provide mono output (terminals are 0.34" wide)

Wiring Recommendation

Wiring Recommendation: This amplifier uses three 25-amp fuses, so its total fuse rating is 75 amps. The Streetwires 4-gauge amp wiring kits (item #s: 211PS4B, 211PS4R, 211PS4BI, 211PS4RI) include an 80-amp fuse, which will accommodate the amp's fuse rating. Other 4-gauge amp wiring kits carried by Crutchfield include a 60-amp fuse. If you are using a 4-gauge amp wiring kit with a fuse rated less than 75 amps, the fuse should be replaced with an 80-amp AGU fuse (item #211AGU80).

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.