JBL MA600 Mono Subwoofer Marine Amplifier

The JBL MA600 is a mono marine subwoofer amplifier designed to add dedicated low-frequency power to a boat audio system. It is suited to installations using a single 2-ohm or 4-ohm subwoofer, or two 4-ohm subwoofers wired for a compatible load. Its compact footprint helps when amplifier mounting space is limited.

This Class D amplifier is intended for boat owners who want to drive a subwoofer separately from full-range speakers. JBL lists output of 350 watts RMS at 4 ohms and 600 watts RMS at 2 ohms, with 1,200 watts maximum power. The mono configuration focuses its available power on bass reproduction rather than multiple speaker channels.

The MA600 provides both low-level RCA and speaker-level input options for use with aftermarket or factory marine stereo systems. Its balanced differential input design is intended to reduce noise and distortion, including susceptibility to radiated engine noise. An adjustable input-level control supports matching the amplifier to the source unit being used.

System tuning is handled with a variable low-pass filter, variable bass boost, and a selectable phase switch. The low-pass crossover can be adjusted from 32 Hz to 320 Hz with a 12 dB-per-octave slope, while bass boost is adjustable from 0 to 12 dB at 45 Hz. These controls help blend the subwoofer with the boat's full-range speakers and enclosure.

A wired remote bass controller is included for convenient bass-level adjustment from the driver's position. The amplifier also includes selectable DC or remote turn-on operation to accommodate different signal setups. Built-in protection circuitry monitors for shorts, overheating, overvoltage, and undervoltage conditions.

Key Features

• Mono Subwoofer Power: Delivers dedicated amplification for a marine subwoofer system.
• Class D Design: Provides efficient output with lower current draw.
• High- And Low-Level Inputs: Works with factory or aftermarket marine stereos.
• Variable Low-Pass Filter: Adjusts subwoofer crossover from 32 to 320 Hz.
• Balanced Differential Inputs: Helps reduce induced engine noise and distortion.
• Included Bass Remote: Allows convenient adjustment of bass output level.

Design & Installation

The MA600 uses a low-profile chassis measuring 8-11/16 inches wide, 2-1/16 inches high, and 7-1/8 inches deep. Its controls and connectors are positioned beneath a removable trim panel, and the amplifier has power and protection indicators. JBL specifies a white finish, a compact chassis layout, and onboard protection circuitry; specific chassis-material details are not published.

Use 8-gauge power and ground wiring as recommended by JBL, and make all connections before permanently mounting the amplifier. Select a mounting location with adequate ventilation, keep the heat sink facing upward rather than downward, and avoid locations where screws or wiring could damage the vessel, fuel lines, or harnesses. Wiring and installation hardware are not included, while mounting screws, input adapters, fuses, and the wired bass controller are supplied.