MJ2955 for power output and MJ3055 for electronic filter, And each channel is 10000UF filter capacitor, Full power pure copper wire toroidal transformer power supply. Input voltage: AC110V or AC23V (50/60hz) . Frequency range: 15HZ- 30KHZ (+/- 3dB) Signal to noise ratio: 93dB Rated power: 15W*2 Class A equivalent Class A and B above 40W. Digital power amplifier above 80W Impedance range: 4 to 8 ohms Harmonic distortion: less than 0.01% 1KHZ. 1W Input port: RCA lotus terminal Size: 336*85*215mm Color: Silver or Gold optional ( please leave a message )