The Zapco ST-204D SQ III is a four-channel wideband Class D amplifier designed for those who prioritize high-fidelity sound quality in their vehicle. It delivers a nominal power of 200W per channel at 4 Ohms, which can increase to 290W at 2 Ohms, or be configured in bridged mode to provide 580W across two channels. This versatility allows you to power a variety of speaker setups while maintaining a frequency response of 15 to 30,000 Hz with low distortion. To help you fine-tune the audio to your cabin's acoustics, the unit includes adjustable electronic filters, a bass boost, and input sensitivity controls. It accepts both RCA and high-level inputs, making it compatible with a wide range of head units. The hardware is housed in a compact chassis measuring 160×58×325 mm, featuring integrated heat sink fins that manage thermal loads during extended listening sessions.