Introducin: Total frequency distortion: 20Hz - 20KHz<0. 1% Frequency response: 20Hz - 20KHz± 0. 5dB Signal noise ratio: >=100dB Intermodulation distortion: <0. 1% Input impedance: 20Kohm Imput levle: 0dB Working voltage: AC220V± 5% 50Hz± 2Hz Technical Parameter: Professional Stereo Power Amplifier. Stereo, bridged and parallel mode. DUAL Variable Speed Fan Cooling. Turn on delay. Over current, over heating and short Protection. Peak, Signal, Bridge&fault LED Indicators. 1/4" & XLR Balanced Inputs. Speakon Outputs. Signal compressor