We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Black rectangular subwoofer amplifier unit with front LCD display

Monoprice Inc.

Monoprice 131029 Subwoofer Amplifier 400 W Black

SKU CH-FD17-55VKP

A 400-watt Class D subwoofer amplifier with DSP presets for crossover, slope, phase and low-cut control

  • TypeAmplifiers & Receivers
  • ColorBlack
  • Weight10.78
  • Features400 watts of deep, hard-hitting power at 4 ohms impedance
  • 400 watts of deep, hard-hitting power at 4 ohms
  • Compact 1U design fits standard racks and tight spaces
  • DSP presets control crossover, slope, phase and low-cut
  • circuit and thermal protection safeguards the amplifier
  • Front-panel backlit LCD screen dims after two minutes of inactivity

Monoprice 131029 Subwoofer Amplifier

The Monoprice 131029 is a 400 watt subwoofer amplifier designed for home audio and home theater systems. It drives medium to large passive subwoofer speakers with high fidelity bass amplification. The unit is stable down to 4 ohms impedance, allowing it to power one or two subwoofers simultaneously. Its compact 1U form factor fits alongside other multimedia equipment.

Installation and common issues

The amplifier features a front panel backlit LCD screen for adjusting user defined presets including crossover frequency, slope, phase and low-cut settings. The screen automatically goes dark after two minutes without adjustments. Built-in short circuit and thermal protection circuits safeguard the unit during operation. Automated power management handles standby and active states without manual switching.

Practical limits of Class D amplification

Class D amplifier topology provides efficient power delivery with reduced heat output compared to traditional designs. The 400 watt rating at 4 ohms defines the maximum clean power available for subwoofer drive. Preset recall allows quick switching between listening scenarios but does not alter the fundamental power or impedance constraints. The amplifier is tailored specifically for subwoofer duty rather than full-range speaker amplification.

Highlights

  • 400 watts of deep, hard-hitting power at 4 ohms
  • Compact 1U design fits standard racks and tight spaces
  • DSP presets control crossover, slope, phase and low-cut
  • circuit and thermal protection safeguards the amplifier
  • Front-panel backlit LCD screen dims after two minutes of inactivity

Specifications

BrandMonoprice
Model131029
Part Number131029
TypeAmplifiers & Receivers
ColorBlack
Weight10.78
Features400 watts of deep, hard-hitting power at 4 ohms impedance

Questions about this item

How do I know the SWA-400 is operating correctly after connecting it?

The front-panel backlit LCD stays active while you adjust settings and goes dark automatically after two minutes with no input, confirming the amplifier is powered and responsive.

What comes in the box with the SWA-400 and what must I supply separately?

The amplifier itself is included; you will need to provide a passive subwoofer speaker (or two) and the speaker cable to connect them, plus a line-level audio source such as a receiver pre-out.

Which version of the 131029 should I choose for my system?

There is only one version of the 131029 — a 400-watt Class D subwoofer amplifier stable at 4 ohms with DSP presets for crossover, slope, phase and low-cut.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.