Input voltage: AC 115V or 230V. Front panel color: Black or silver. Frequency Response: 20Hz -0.3 DB, 20KHz -0.5 DB. Output power: 250W RMS 4 ohm. Voltage gain: 31 times. Input Sensitivity: 1.5V. Output power tube: using original ST 2SC5200 (230V 15A, 150W) 4 PCS per channel. The PCB has its own rectification filter and speaker protection circuit. Size: 320mm255mm75mm (WDH) not include the feets and terminals dimensions. Weight: About 7.3KG. Note: the package are not come with the power cable.