This is an awesome circuit that was created by RunOffGroove and this layout was made by OftenFX. This effect is based on a popular Supro amp and this pedal captures much of the amp’s tone. This is a FET-based design and I would classify it as a low gain / medium gain pedal. It has a built on charge pump to run the pedal at 18v from a standard 9v adapter. It has a great vintage rock and roll sound to it.

Voltages:
Q1 J201
G 0v
S 0.4v
D 11.8v
Q2 J201
G 0v
S 0.4v
D 11.7v
Q3 J201
G 0v
S 0.4v
D 11.9v