... Equalizer, Audio Opal, EQ,High-Pass Filter; BSS FCS-966 Graphic Equalizer, Audio Opal, EQ,High-Pass FilterBrief Instrution:BSS Audio ... a high-quality relay switches the input signal directly to the output connectors.Control Descriptions* Faders - 30 EQ filter faders ... detent on 45mm long-throw precision faders * HP Filter - Sweepable high pass filter, frequency adjustable from OUT (flat) up to 250Hz ...