... Opal, EQ,High-Pass Filter; BSS FCS-966 Graphic Equalizer, Audio Opal, EQ,High-Pass FilterBrief Instrution:BSS Audio provides ... the Opal FCS-966 Constant Q Graphic Equalizer with separate LF and HF contour filters that can change ... -24dBu to +18dBu in 8 stepsBSS Audio Opal FCS-966 Graphic Equalizer Specifications:HP filter set to OUT. GAIN, HF, LF & all ...