Product Details:The CQ31 combines a 31-band single channel EQ with a fully adjustable optical compressor for extra control. When fine band-resolution is required, turn to the CQ31, with a full 31 bands (1/3-octave) of EQ with selectable ±6dB/±12dB range. Topped off by a fully adjustable optical compressor, the CQ31 is ready for the challenges of live sound, fixed installations, DJ racks, and more. Double 'em up for the ultimate in stereo EQ control.