Input interface: U disk, RCA, Bluetooth, optical fiber, coaxial Treble and bass adjustment range: 6dB Preamplification: tube GE5654*2 Power amplifier: NE5532*2, MA12070 Bluetooth U disk chip: BP1048 Frequency response range:18-25khz Distortion: 0.003% Signal-to-noise ratio: 105dB Main parameters of the headphone amplifier Distortion: D+N: 0.004% (RLGreater than 10 k) Distortion:+N:0.020%(RL=32) Signal-to-noise ratio: 99 dB Dynamic range: 99 dB Maximum power of headphone amplifier: 125mW+125mW Maximum power of power amplifier: 80W+80W (4 ohms), 40W+40W (8 ohms) U disk supported formats: MP3/WAV/APE/FLAC, sampling rate: 16bit/48khz Working voltage: DC 24V Standby power:Less than 0.5W Plug Type: US Plug, it applies to Canada, India, Mexico, Thailand, Taiwan, the , the Philippines and so on. Voltage: AC110V Colour:Black Material:abs Package Contents: 1 x Amplifier Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.