Supro Boost is a J-FET based pedal that delivers up to 20d B of noiseless gain boost plus optional treble cut or bass cut to contour your sound. The Supro Boost pedal sports a simple control layout with a single Volume knob & an oversized toggle switch to select BRIGHT, FLAT or DARK overall frequency response. The BRIGHT mode enables a 6d B / octave HP (high pass) filter for thinning out humbucker guitars when adding boost to increase sparkle & prevent mud. The DARK mode enables a 6d B / octave LP (low pass) filter for fattening up single coil guitars when adding boost to increase warmth & prevent harshness. Taking the boost pedal one step further, the Supro Boost offers a TRS port for expression pedal control of the VOLUME knob. Technische Daten Frequency linear boost up to 20db 6db per octave High Pass Filter option 6db per octave Low Pass Filter option Expression pedal control for VOLUME Accepts standard 2.1mm neg. tip power supply Runs on 9V battery (included) Current Draw below 20m A Original circuit design by Thomas Elliott