This is the circuit diagram of BOSS Slow Gear SG-1 effect for electric guitar.
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.
The SG-1 filters out the attack of your note, and swells the volume automatically. There are only 2 controls, one for the attack speed, and the other for sensitivity. The attack knob controls the speed of the volume swells. A compressor or overdrive in front of it may be helpful to minimize the variations in your signal level for the SG-1’s response. Used with a delay it sounds sort of like a more articulated E-bow or a passage played backwards.
Download the BOSS Slow Gear SG-1 circuit diagram in PDF version:
This is the other circuits of BOSS Slow Gear: