JL Audio AP300/1 300W RMS Class D Monoblock Marine Subwoofer Amplifier, Ignition-Protected, IP67 (010-03428-00)

Add powerful, controlled bass to your marine audio system without giving up valuable installation space. The JL Audio AP300/1 is an ultra-compact monoblock Class D amplifier designed specifically for a marine subwoofer. It offers the efficiency of Class D amplification, an integrated LCD setup interface, and an ignition-protected housing engineered for marine environments.

At a 14.4V supply, the AP300/1 provides 200W RMS into 4 ohms or 350W RMS into 2 ohms, with a manufacturer-described 300W power class. Selectable input sensitivity, adjustable low-pass filtering, bass boost, and a defeatable infrasonic filter allow the bass system to be tailored to its installation. When paired with a compatible Fusion DSP stereo, Easy Tune profiles can streamline system setup through the Fusion Audio app.

Key Features

• Compact Subwoofer Amplification: A single Class D channel intended to power a compatible marine subwoofer.
• Up to 350W RMS at 2 Ohms: Also delivers 200W RMS at 4 ohms, measured at 14.4V DC with less than 1% THD.
• Built-In LCD Controls: Integrated screen and buttons allow setup without conventional exposed adjustment knobs.
• IP67-Rated Chassis: Water- and dust-resistant amplifier housing; rating excludes cables.
• Ignition Protected: Designed for installations requiring ignition-protected marine electrical equipment, subject to manufacturer guidance.
• Easy Tune Capable: Supports compatible Fusion DSP stereo and Fusion Audio app tuning profiles.
• Subwoofer Signal Processing: Adjustable low-pass crossover, bass boost, defeatable infrasonic filter, and output polarity control.
• Electrical Protection: Protection against abnormal input voltage, overheating, and output short circuits.

General Specifications

• Amplifier Type: Monoblock marine subwoofer amplifier
• Amplifier Class: Class D
• Channels: 1
• Operating Voltage: 9–16V DC
• Rated Power at 4 Ohms: 200W RMS x 1 (14.4V, <1% THD)
• Rated Power at 2 Ohms: 350W RMS x 1 (14.4V, <1% THD)
• Frequency Response: 10Hz–500Hz (+0, -1dB)
• Signal-to-Noise Ratio: >70dB (A-weighted, referenced to 1W)
• Input Sensitivity: 200mV–2V RMS (Low); 800mV–8V RMS (High)
• Input Impedance: 20kO (Low sensitivity range); 11kO (High sensitivity range)
• Standby Current: <1mA
• Idle Current: Approximately 700–750mA
• Recommended Fuse Rating: 35A
• Recommended Fuse Types: AFS, AGU or MaxiFuse
• Minimum Copper Power/Ground Wire: 4 AWG (per published specification)
• Low-Pass Crossover: 20Hz–500Hz, 12dB/octave
• Bass Boost: 0 to +18dB at 37Hz
• Infrasonic Filter: 20Hz–50Hz, defeatable
• Output Polarity Switch: Yes
• Water and Dust Rating: IP67 (amplifier chassis only; cables excluded)
• Operating Temperature: -4°F to 149°F (-20°C to 65°C)
• Dimensions: 10.43" W x 4.90" D x 1.86" H
• Manufacturer Warranty: 3 years

Compatibility

Designed for a compatible marine subwoofer and 9–16V DC electrical system. Select a subwoofer load appropriate for the amplifier's supported 2-ohm or 4-ohm output ratings. Easy Tune functionality requires a compatible Fusion DSP-equipped stereo and the Fusion Audio app; other sources may be used with manual amplifier configuration. This monoblock model is not intended to replace a multi-channel full-range speaker amplifier.

Installation Notes

Use a correctly rated externally fused power connection, suitable copper cable, and marine-appropriate mounting practices. The amplifier does not have an internal replaceable fuse. Confirm the power/ground connection requirements and installation clearances in the supplied instructions. The IP67 rating does not extend to exposed cable ends or other connected equipment.