Power Output: 2 x 500mW x 2 @ 100 Ohm load, Class A DAC Resolution: 16 bit 44.1kHZ Vacuum Tubes: 1 x 6N2 THD: Less or equal 0.1% @ 100 Ohm (1kHz, 300mW) Signal/Noise ratio: 88dB Input Sensitivity: 750mV Inputs: RCA stereo AUX, USB for PC Headphone Impedance: 30 to 300 Ohm Included Accessories: USB cable, DC Adapter DC Power, Power Consumption: 18V 1A Dimensions (H x W x D): 5 x 15 x 11.5 cm Weight (net): 0.8 kg / pcs.