Specification Vacuum Tubes:101Dx1, 6SN7x4, 5AR4x1 Output: 3V. (Max 28V) Frequency Response: 3Hz~100KHz Input Impedance: 250KΩ T.H.D.:0.02% Channel Balance: <0.5 db(20Hz~100KHz Total Gain: 20db S/N:>90db Weight: 30 Kg Input Voltage:220~240V