EMP Professional EBK57 1200W Karaoke Echo Power Mixing Amplifier w/Remote/USB/SD/MP3/WMA Player Bulit-in karaoke echo effect with remote control, | Auto and manual volume reset control switch, | Karaoke and main channel 32 bit digital key controller. Output power(4:L 200W+R200W | Mic input sensitivity10mV, | External device sensitivity:200mV S/N ratio80dB | T.H.D:0.1% | Frequency band:25Hz~20KHz | Mic.tone adjustmentLOW:80Hz15dB | Mic.tone adjustmentMID:3.5KHz12dB Mic.tone adjustmentHI:12KHz15dB | Echo.tone adjustmentLOW:80Hz15dB | Echo.tone adjustmentHI:12KHz15dB | Music.tone adjustmentLOW:100Hz15dB Music.tone adjustmentMID:1KHz12dB | Music.tone adjustmentHI:10KHz15dB | Power source:100V/60Hz