Product Detail Feedback Detection System instantly reveals critical frequencies Built-in limiter control from -20 dB to +20 dB (OFF) Variable low cut filter: (Off)10 to 400 Hz ; and high cut filter: 1.25 to 20 kHz (Off) Dedicated mono subwoofer output with adjustable crossover frequencies . The "Phonic 2 Rack Unit Dual-Channel Digital 31-Band Graphic Equalizer IA231F" is best product for you. We recommended Phonic 2 Rack Unit Dual-Channel Digital 31-Band Graphic Equalizer IA231F