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Wanna make some noise? With the 401DB mono subwoofer amp from Coustic, you've got what it takes! The proprietary Class D output stage delivers maximum power with minimal current draw from your car's electrical system. You end up with an amp that runs cooler, sounds cleaner, and slams harder.

Booming bass is what the 401DB is all about. It puts out a cool 200 watts RMS into 4 ohms, and doubles the output to 400 watts at 2 ohms. A variable low-pass filter and slammin' low-frequency boost combine to give your music the bass infusion you've been dreaming of. The selectable subsonic filter (off, 20 Hz, 40 Hz) improves system performance by removing super-low bass that your speakers can't reproduce.

Wanna save some cash? Check out this powerful Coustic bass system. It pairs the 401DB amp with a Coustic BP12X2D dual 12" subwoofer enclosure for some neighbor-shaking bass.

Product Highlights:

  • 200 watts RMS x 1 at 4 ohms
  • 400 watts RMS x 1 at 2 ohms
  • Class D design
  • MOSFET power supply
  • two 30-amp fuses
  • requires 4-gauge power and ground leads — wiring and hardware not included with amplifier
  • variable low-pass (40-200 Hz) crossover, 36 dB/octave
  • 0-18 dB variable bass boost at 45 Hz
  • defeatable subsonic filter (20 or 40 Hz)
  • preamp- and speaker-level inputs
  • preamp outputs
  • protection circuitry guards against voltage spikes, oscillation, DC offset, short circuit, and excessive heat buildup
  • 13-3/16"W x 2-5/16"H x 11-1/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

Coustic 401DB Reviews

Hands-on research

What's in the box?

Download owner's manual

  • Mono-block amplifier with two 30A fuses inserted in chassis
  • 12" Speaker-level input harness
  • 4 Self-tapping screws (3/4" length)
  • Owner's manual (English/French)
  • 2 Coustic decals

Product Research

Inputs and Outputs Notes


Class D Design: The Coustic 401DB is a Class D amplifier. The proprietary Class D output stage delivers maximum power with minimal current draw from the vehicle's electrical system while eliminating traditional Class D interference.

Power Supply: High-current MOSFET transistors are used in the power supply section to minimize internal heat and maximize reliability. The combination of the very high pulse-width-modulated (PWM) switching frequency and the extra large filter capacitors delivers stronger and deeper transient bass response.

Crossover: The amp is equipped with a continuously variable 40-200Hz low-pass filter with a steep 36dB/octave slope. This low-pass filter is not defeatable; it is constantly on.

Subsonic Filter: The amplifier's subsonic filter eliminates ultra-low, inaudible frequencies to protect your speakers from damaging over-excursion of the cone and to improve the amp's efficiency. The 3-way switch allows you to choose a cutoff frequency of 20Hz or 40Hz, or turn the subsonic filter off. Note: No slope information is given for the subsonic filter.

Protection Circuitry: The sophisticated protection circuitry monitors abnormal conditions, such as voltage spikes, oscillation, DC offset, short circuit, or excessive heat buildup. When any of these undesirable conditions exceed their respective preset limits, the circuit will shut down the audio system briefly and the protection indicator lights up to identify the problem for immediate attention. Note: The power and protect LED glows green to indicate that the amplifier is on and operating normally. It glows red to indicate when there is a problem that needs to be rectified.

Inputs and Outputs Notes

Power/Ground Terminals: The 401DB is equipped with 0.475"-wide power, ground, and remote screw terminals that can accept up to 4-gauge bare wire or with ring or spade connectors.

Speaker Terminals: The amplifier provides 0.348"-wide screw terminals to two speakers. For single-subwoofer systems, only one set should be used. Both sets of terminals output a mono signal, and are wired internally in parallel (total speaker load should be 2 ohms or higher). They will accept up to 8-gauge bare wire or with ring or spade connectors.

Speaker Level Inputs: If you're connecting the amplifier to a receiver or factory radio without preamp outputs, you can use the supplied Speaker Level Input harness. You will need to splice the receiver/radio's speaker wires to the harness, then simply plug the harness into the multi-pin Molex jack on the amplifier.

Line Outputs: The line outputs can be used to feed signals to another amplifier without having to split the signal or use Y-adapters. They are not affected by the built-in low-pass filter.

Remote Control Port: The amp has a built-in remote subwoofer level control input port, a 3.5mm (1/8") mini-jack, compatible with an optional R S remote control (available from the manufacturer).

Our Product Research Team

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