Infinity Marine M3004A 4-Channel Marine Amplifier

The Infinity Marine M3004A is a four-channel marine amplifier designed to add dedicated power to a boat audio system. It can drive four full-range speakers, or it can be configured for bridged operation when a system needs more power for fewer channels. It is intended for marine stereo upgrades where head-unit power alone is not enough for clear playback at higher listening levels.

With 75 watts RMS per channel at 4 ohms and 100 watts RMS per channel at 2 ohms at 14.4V, the Marine M3004A provides flexible power for compatible marine speakers. Its four-channel layout supports front and rear speaker zones, while bridged operation supports two 4-ohm loads. This makes it useful for systems ranging from a straightforward four-speaker setup to a mixed speaker-and-subwoofer configuration.

The amplifier uses Class H amplifier technology to provide substantial output while managing current draw. Balanced differential inputs are designed to help reduce noise and distortion, including noise that can be introduced by an engine or electrical system. Variable high-pass and low-pass crossovers let the installer tailor the frequency range sent to the front and rear channels.

Integration options include both low-level preamp inputs and high-level speaker inputs, allowing the amplifier to work with aftermarket or factory marine stereos. Adjustable input sensitivity accommodates a range of source-unit output levels. Full-range preamp outputs also allow an additional amplifier to be added without relying on RCA splitters.

The Marine M3004A is built for practical system expansion and protected operation. Its onboard circuitry monitors for short circuits, excessive temperature, overvoltage, and undervoltage conditions, with a power/protect indicator to help identify an operating fault. For boat owners planning a cleaner, more capable multi-speaker system, it provides channel flexibility, crossover control, and expansion capability in one compact amplifier.

Key Features

• Four-Channel Output: Powers four speakers or supports bridged two-channel operation.
• Class H Amplification: Delivers strong output with managed current draw.
• Balanced Differential Inputs: Helps resist induced engine and electrical-system noise.
• Variable Crossovers: High-pass and low-pass filtering supports system tuning.
• High- And Low-Level Inputs: Connects to factory or aftermarket marine stereos.
• Protection Circuitry: Monitors shorts, temperature, overvoltage, and undervoltage conditions.

Design & Installation

The Marine M3004A uses a compact amplifier footprint measuring 12-5/8 inches wide, 2-3/16 inches high, and 7-1/8 inches deep. Its control layout includes separate front and rear gain and crossover adjustments, along with front/rear input connections and full-range preamp outputs. A removable panel cover and included mounting screws support a tidy installed appearance.

Install the amplifier in a secure location with adequate airflow and clearance on both sides of the mounting surface. Infinity recommends 8-gauge power and ground leads; wiring and installation hardware are not included. Connect it through either low-level RCA signals or the supplied bare-wire-to-RCA adapters for speaker-level input, then set gain and crossover controls to suit the connected speakers and system layout.