Memphis MX400-4 4-Channel Powersports Amplifier

The Memphis MX400-4 is a compact four-channel powersports amplifier designed to add dedicated amplification to compatible off-road, side-by-side, and marine-style audio systems. It provides four amplified channels for full-range speakers, helping a system achieve stronger output than a source unit can typically supply on its own. Its compact housing supports installations where available mounting space is limited.

This amplifier is intended for riders and installers building or expanding a powersports audio system with multiple speakers. It delivers 75 watts RMS per channel at 4 ohms or 100 watts RMS per channel at 2 ohms, making it suitable for matching with compatible full-range speakers. It can also be bridged to provide two 200-watt RMS channels at 4 ohms.

The MX400-4 is built for applications exposed to water, dust, and changing outdoor conditions. Its IP66-rated water and element resistance, conformal-coated circuit board, and sealed connectors support use in demanding powersports environments. A protective cover over the top-mounted controls helps keep the tuning area shielded while maintaining access during setup.

For system tuning, the amplifier includes a fixed 80 Hz crossover and supports both high-level and low-level input compatibility. Its 2/4-input switch can simplify signal routing when connecting compatible audio sources. The 10 Hz to 20 kHz frequency response allows the amplifier to cover the normal full-range signal spectrum used by compatible speaker systems.

The MX400-4 fits naturally into a staged powersports upgrade, whether powering four speakers directly or operating as a bridged two-channel amplifier. It is specified for use with Memphis' recommended 8GKIT amplifier wiring kit. Proper speaker impedance, secure mounting, and protected power wiring are important for a reliable installation.

Key Features

• Four-Channel Output: Powers up to four compatible full-range speakers.
• 75W x 4 RMS at 4 Ohms: Provides continuous power for properly matched speakers.
• 2-Ohm Stable Operation: Delivers 100W x 4 RMS at 2 ohms.
• Bridgeable Channels: Supports 200W x 2 RMS at 4 ohms.
• IP66 Resistance: Helps protect the amplifier from water and elements.
• Fixed 80 Hz Crossover: Provides a defined crossover point for system setup.

Design & Installation

The MX400-4 uses a compact chassis measuring 8.75 by 3.25 by 1.75 inches. Its conformal-coated board, sealed connectors, and protected top-mounted controls are designed for powersports applications where exposure resistance and packaging flexibility matter. The amplifier carries an IP66 water- and element-resistance rating.

Install the amplifier in a secure location with appropriate ventilation and protected wiring paths. Use compatible high-level or low-level source connections, match speakers to supported 2- or 4-ohm operation, and use the recommended 8GKIT wiring kit. When bridging channels, use a 4-ohm speaker load per bridged channel pair and follow the manufacturer wiring guidance.