The Snow White Auto Wah (SWAW) circuit is based on a 1991 BJF rack mount remote wah circuit and is tuned like a real wah. The circuit was redesigned with envelope controls and built into small size pedal. It has very fast tracking and accuracy rarely found on auto wahs/ envelope filters. With the four knobs you can have total control of the effect. SWAW works both with guitar and bass and you can fine-tune the pedal to suit your instrument, your playing style and your taste of tone. The pedal has a unique decay control for the filter frequency fall speed. You can set it to be fast for wah effects on every note, or slower for a more traditional auto wah sound. Like all Mad Professor pedals SWAW is hand made in Finland using only premium components, to give years of trouble free operation with superb musical tone.