Upgraded version of single channel amplifier board 1943+5200 high-power Toshiba transistor rear stage amplifier board. The board is a single channel rear amplifier board that requires dual channels. please buy 2 pieces, The circuit design uses the A970/C2240 high voltage audio pair dual differential circuit and A1145/C2705 for voltage amplification, promoting the use of medium power pair A1837/C4793, and the output stage uses A1943/C5200 high-power Toshiba pair. Wide power supply range, DC positive and negative 20V-90V can be used, as long as sufficient power is supplied, it can easily reach 300W. Good sound quality, extremely powerful driving force, driving 15 inch speakers without any pressure! Amplifier board size: 195X60X45 MM length * width * height Real power: undistorted power 400W, maximum power 600W.. Power supply: dual voltage, DC positive and negative 20-90V (upgraded version has optimized the circuit and parts, can To directly apply high voltage, it is recommended to use a voltage below 90V and not challenge the voltage limit Package Included: 1pcs 400w audio amplifier board