231 equalizer TRS or XLR difference balance input and output; You can choose body force sound or ultralow sound which is composed by adding left and right channels. Both channels have *10 range selection switches, and both channels have 40Hz high channel filter (low frequency resection). All outputs have phase reversal switches. On average, the output power on all frequency bands can be independently adjusted dB/ linkwi-tz-riley filter (professional standard); The voice/mono state indicates LED lights, indicating the working mode of unit selection; Optional range of lift/decay: + / -6db and + / -15db, electronically balanced non-balanced input, servo balanced/non-balanced output; The input and output are provided with the rf filter XLR, the alignment terminal and 1/4TRS interface, -12db +12dB input gain range, and 18dB/ frequency multiplier.