Upgraded version of the mono 1000W amplifier board 1943 + 5200 high-power Toshiba pair of tube rear amplifier board; 1. Board for mono rear amplifier board, need to dual-channel, buy 2 pieces. 2. Circuit design using A970/C2240 high voltage audio tube dual differential circuit and A1145/C2705 for voltage amplification. Push the use of medium power tube A1837/C4793, the output stage using A1943/C5200 high-power Toshiba tube. 3. Wide range of power supply, DC plus or minus 20V-90V can be, as long as enough power to easily reach 800W sound quality, driving force is extremely strong, to promote 15-inch speakers, no pressure! 4. Size: 200 * 75 * 45 L * W * H Weight: 440g 5. Power: undistorted power 800W, peak power: 1000W. Power supply: dual-voltage, DC plus or minus 20-90V (upgraded version has been optimised circuitry and parts, can be directly on the high voltage, it is recommended that the use of 90V or less, do not challenge the voltage limit.) When ordering, please leave a message in the order, what is the voltage you use, so that we can give you the most suitable effect debugging. Independent speaker protection power supply 12V (AC, DC) input.