4-Channel Class D Amplifier

The Harmony Audio HA-A400.4 is a 4-channel Class D amplifier designed to deliver maximum power output with high efficiency. Its Class D circuitry ensures reliable operation and effective heat management, making it a robust choice for powering your vehicle's audio system. With a frequency response ranging from 10Hz to 30kHz and a signal-to-noise ratio of 95dB (A-weighted), this amplifier is built to provide clear and powerful sound reproduction. Installation is made easier with the included HA-EASY adapter, which allows for seamless integration with factory or aftermarket head units. This adapter enables direct splicing into factory speaker wires for audio input and provides a convenient solution for amplifier turn-on/off without needing a separate 12V switched remote wire in most applications. This feature can save significant installation time and reduce the need for complex wiring harnesses. Beyond basic connectivity, the HA-A400.4 offers versatile control over your audio. It supports both DC Offset and traditional 12V remote turn-on methods. User-adjustable settings include selectable filters (Full, High Pass, Low Pass) for front and rear channels, variable gain control, and a selectable input type supporting high or low-level signals. Additional features like a bass boost (0dB - 12dB @ 50Hz) and variable low-pass and high-pass filters further allow for fine-tuning your system's sound profile. The amplifier boasts impressive power handling capabilities: 75W RMS x 4 channels at 4 Ohms stereo, 85W RMS x 4 channels at 2 Ohms stereo, and 200W RMS x 2 channels when bridged at 4 Ohms. Its compact dimensions (8-5/8" L x 6-1/8" W x 2" H) make it suitable for installation in various locations within a vehicle. The brushed aluminum case with a light-up blue LED Harmony logo adds a stylish touch, and power/protection lights provide at-a-glance status information.