Specifications: Power Output: 18 watts RMS x 2 into 4 ohms Total Harmonic Distortion: <1% @ 18W per channel Minimum Speaker Impedance: 4 ohm Frequency Response: 20-20,000 Hz, ±2 dB Channel Separation: 65 dB Dynamic Range: >80 dB Signal-to-Noise Ratio: >80 dB Preamplifier Tube: 6F2 x 2 Headphone Amp Output: 32 ohms; 20 mW (maximum @ 1 kHz, <1% THD+N) Bluetooth Version: 5.0 Input Impedance: 47k ohms (minimum) Input Sensitivity: 300 mV Switching Voltage: 100-240V Product dimension:L234*W158*H97(MM) NW:1.2KG GW:1.6KG Master-carton dimension(4 Stes):L440*W295*H350(MM) Master-carton GW(4 Stes):7.5KG