The Slow Gear SG-1 effect sounded like a guitar player riding the volume knob of the guitar. This produced a cool swelling sound with a gradual attack, almost like a violin. At $99.50 original retail price, the Slow Gear was a popular pedal, and players still seek out this BOSS classic in pawn shops and classified papers today.
With above circuit diagram, you can build the BOSS Slow Gear device by yourself and no need to pay a lot for this circuit.
Download the BOSS Slow Gear SG-1 circuit diagram in PDF version:
This is the other circuits of BOSS Slow Gear: