MEMPHIS MX400-4 4-Channel Powersports Amplifier

The Memphis MX400-4 is a compact four-channel powersports amplifier designed to add clean, flexible amplification where space is limited. It is built for side-by-side, ATV, motorcycle, and similar off-road audio installations that need more output than a source unit can provide. Its weather-resistant construction helps support dependable installation in exposed vehicle environments.

With 75 watts RMS per channel at 4 ohms or 100 watts RMS per channel at 2 ohms, the MX400-4 can power front and rear speakers from one compact chassis. It can also be bridged to two channels at 200 watts RMS each into 4 ohms. This makes it useful for full-range speaker systems, or for systems that need a more focused two-channel configuration.

The amplifier uses efficient Class D technology and has a 10 Hz to 20 kHz frequency response for full-range system use. Independent front and rear sensitivity controls allow the amplifier to be matched to the output level of the source unit. A selectable 2-channel or 4-channel input mode can simplify wiring when the source provides only one pair of audio outputs.

Its IP66-rated chassis, conformal-coated circuit board, and sealed connectors are engineered for resistance to dust, water spray, and the elements. A protective top cover shields the tuning controls while keeping them accessible after installation. The compact chassis is especially practical for tight mounting locations common in powersports vehicles.

The MX400-4 accepts both low-level RCA and speaker-level input signals, helping it integrate with aftermarket or factory-style source units. Fixed 80 Hz high-pass and low-pass crossover options help direct the appropriate frequency range to connected speakers. Pair it with properly matched speakers, a suitable 8-gauge amplifier wiring kit, and a fused power connection for a complete powersports audio upgrade.

Key Features

• Four-Channel Output: Powers up to four speakers from one compact amplifier.
• Class D Design: Provides efficient full-range amplification for powersports systems.
• IP66-Rated Chassis: Helps resist dust, water spray, and outdoor conditions.
• Conformal-Coated Board: Adds protection for internal electronics in exposed installations.
• Fixed 80 Hz Crossovers: Supports high-pass, low-pass, or full-range channel setup.
• High- And Low-Level Inputs: Connects with RCA-equipped or speaker-level source units.

Design & Installation

The MX400-4 uses a compact weather-resistant chassis with sealed connectors, a conformal-coated circuit board, and a protective cover over its top-mounted controls. These details support use in powersports applications where vibration, dust, and water exposure are common considerations. Its status LED indicates normal operation or protection status.

Mount the amplifier in a secure location with practical access to the control cover and adequate cable routing. The recommended Memphis 8GKIT wiring kit is specified for installation, while an 8-gauge power and ground connection with a 40A fuse is recommended. Use the included input harness that matches the source signal type, select 2-channel or 4-channel input mode as needed, and set each channel pair to high-pass, low-pass, or full-range operation.