The Mk1 Tonebender was a 3 transistor fuzz circuit based loosely on the famed Maestro FZ-1 (that ran on AA batteries!). We have used vintage, NOS Germanium transistors to replicate the awesome sizzling sustain of the original units in a more modern package. We've modernized the circuit on a small, beautifully laid-out PCB, used low-noise, high-quality components, and we hand select the transistors for noise floor and sonic accuracy.
We always recommend isolated power supplies. If you daisy chain effects on one supply, you may inject noise, ripple, ground loop hum, etc. This effect requires 9v, center negative power. In other words, the industry standard power supply.