Audiotek AT-4000M 4000W Monoblock Car Amplifier

The Audiotek AT-4000M is a one-channel monoblock car amplifier designed for adding a dedicated bass channel to a vehicle audio system. It is intended for use with subwoofers and supports a 2-ohm speaker load. Its compact, surface-mount format makes it suitable for trunk, rear-seat-back, or other secure installation locations with adequate ventilation.

This amplifier is a practical choice for listeners building a subwoofer system that needs adjustable low-frequency output. A continuously variable low-pass crossover helps limit the amplifier’s output to bass-focused frequencies. The included remote subwoofer level control allows convenient adjustment of bass output from the driver’s position.

The AT-4000M is specified for up to 4000 watts maximum power and uses a Class A-B amplifier design. Its MOSFET pulse-width-modulated power supply is designed to provide the amplifier’s operating power. Continuously variable input gain adjustment helps match the amplifier to the output level of the connected source unit.

For system flexibility, the amplifier includes nickel-plated RCA inputs as well as speaker-level inputs. This allows it to be integrated with audio systems that provide either low-level RCA signals or amplified speaker outputs. A remote turn-on/turn-off circuit supports connection to a vehicle audio system’s switched remote-output lead.

The AT-4000M uses an aluminum-alloy heat sink to support heat dissipation during operation. Thermal and speaker-short protection circuitry are included to help safeguard the amplifier and connected system. LED power and protection indicators provide a quick visual status check after installation.

Key Features

• Monoblock Design: Provides one dedicated amplified channel for a bass-focused system.
• 4000W Maximum Power: Supplies a manufacturer-listed maximum output of up to 4000 watts.
• 2-Ohm Stability: Supports operation with a 2-ohm speaker load.
• Variable Low-Pass Crossover: Helps tailor output for subwoofer-frequency playback.
• Remote Bass Level Control: Lets the driver adjust subwoofer level conveniently.
• Protection Circuitry: Includes thermal and speaker-short protection for system monitoring.

Design & Installation

The amplifier features a heavy-duty aluminum-alloy heat sink and LED power/protection indicators. Its Class A-B circuit design uses a MOSFET pulse-width-modulated power supply, soft turn-on circuitry, and nickel-plated input connections. The chassis is designed for surface mounting.

Install the AT-4000M on a secure, dry surface with sufficient airflow around the heat sink, and disconnect the vehicle battery’s negative terminal before wiring. Connect it to a compatible 12-volt vehicle electrical system, use either RCA or speaker-level input as appropriate, and wire the connected subwoofer system so its final load is not below 2 ohms. Set gain, low-pass crossover, and bass boost conservatively during initial setup, then use the included remote level control for day-to-day bass adjustment.