This is one piece of bare board of a MOSFET power amplifier, with a well-proven good performance architecture. The input is responsible by two pairs of transistors in a fully complementary structure. The output is responsible by two pairs of MOSFETs to ensure a high power output and high headroom for bass attack. The circuit also includes DC servo to minimize the output DC. In terms of board design, the output transistor pads are designed such that users can pick either the G-S-D pin out transistors, such as 2SK1058/J162, or the G-D-S pin out ones, such as 2SK1529/J200. It is because those pads on the PCB are not hard wired to the circuit board. With different transistors' different pin out, Users can simply jump the leads at the bottom of to the appropriate circuit track. This is shown in one of the picture. A schematic without value is here to show the architecture. Performance-wise , the amplifier gives very natural high frequency and authentic bass when biased as a class AB amplifier. With class A biasing ( need appropriate heatsink to dissipate the heat) the amplifier gives very much tube-like sound that can provide never-fatique sound. Board dimension : 150mm x 75mm Board thickness : 2mm. Copper thickness : 70um - 4 times of normal board copper thickness ! This is one piece of power amplifier board for one channel only. For stereo application two boards are needed. We provide schematic and part list to buyers by EMAIL. We do air shipping worldwide at US$6.00. We welcome combine shipping. Powered by SoldEazy