KR Sound
Well-known member
This seems pretty cool.
“Happy #FuzzFriday! We just posted a Fuzz Face bias calculator to the tech articles section of our website. The calculator works for silicon and germanium transistors (or a combination), and any pedal that uses the same topology - Fuzz Face, Schaller Fuzz, Q2 & Q3 of the Tonebender Mk2/Supa Fuzz, etc.
With some of the more extreme transistor specs, like high leakage or very low beta, some of the other available calculators start to output impossible numbers. This one should remain very accurate with any realistic spec you throw at it.
This calculator also has the option to automatically fill in the relevant fields with circuit values from popular Fuzz Face variants. This allows you to enter your transistor specs and then try out various surrounding circuits to see if those transistors will bias well in various stock fuzz circuits - Fuzz Face, Vox Tonebender, D*A*M Meathead, Moreschi Fuzz Wah, Cornell First Fuzz, Top Gear Fuzz, etc.
We are in the process of putting together an accompanying article which goes in-depth on the factors that play into bias in various common fuzz and audio transistor circuits, which should help readers understand how to design around particular transistor specs, how negative factors like temperature sensitivity can be mitigated, what is required to bias different variations of the circuits, etc. We will post an update in the near future when that is ready.”
