HIFI PASS ACA Stereo single-Ended 5W+5W Class A FET+MOS Power Amplifier

About this deal

This is a finished, ready-to-use stereo power amplifier inspired by the Pass ACA (Amp Camp Amp) circuit design. It delivers 5W per channel in single-ended Class A operation , making it well suited to audiophiles who prefer the warm, low-distortion character of Class A solid-state amplification at modest power levels. With around 6.5 times voltage gain, it is best matched with efficient speakers of roughly 90dB sensitivity or above, such as desktop or bookshelf speakers. The circuit uses a FET input stage feeding a MOS output stage in the classic PASS two-stage topology. An OCL output structure means no speaker protection circuit is required in the signal path. Each channel runs as a fully independent mono structure , and the input stage uses Nichicon MUSE BP coupling capacitors, with a large output coupling capacitance to improve low-frequency performance. As a Class A design, the amplifier runs warm during use, so adequate ventilation around the unit is recommended.