Toggle between NPN/PNP modes with the flick of a switch.
Finally a pedal that answers the question which fuzz should I have on my board. “Do I want the soft attack and warmth of Germanium PNP or the harder edges and sustain of the Silicon NPN?” With this you get to have both in a nice little package.

Independent bias controls for each pair allow you to combine Silicon and Germanium operation into one pedal.
When biasing the Twin Face, set your DMM to read DC voltages and place your black probe in the screw hole of your enclosure for ground and place your red probe on the collector of Q2. Adjust the trimmer on until you reach roughly 4.5V on the NPN side and -4.5V on the PNP side.

Onboard voltage inverter allows NPN or PNP operation from a standard center-negative 9VDC power supply.
No need for multiple power supplies or grounding issues when used in a daisy-chain.

Controls

Fuzz – Adjusts the amount of fuzz
Volume – Controls the output volume
NPN/PNP (Toggle switch) – Toggles between NPN and PNP transistors
Specifications

Onboard Voltage Inverter – Runs on standard 9VDC pedal power, no grounding issues in pedal chain