Quote:
Originally Posted by Craig Sawyers
The original fuzz face operates with a first transistor collector current of about 0.25mA, and the second transistor with about 0.38mA for a beta of 90.
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Some years ago, I got fed up with my old germanium Fuzz Face making strangled fart noises when it got warm. I came up with a fairly simple automatic bias adjustment circuit that compensated very effectively for the change in the transistor characteristics, and kept the collector voltage of the second transistor nailed to 4.6V over a very wide range of temperatures - I'll post it if anyone's interested.
The other approach I tried (successfully) was building the standard Fuzz Face circuit with silicon low gain transistors (I used 2N2369A RF devices or two of the transistors in a CA3049 transistor array IC). The trick is to bypass the base to the collector of each transistor with a small value capacitor. This gets rid of the high frequency nastiness! It's worth experimenting with the values until you get something that sounds good. 220p or 330p are good starting points.
The acid test was to take a germanium Fuzz Face and the modified silicon one to our local rehearsal studio. None of the musicians who tried them could tell the difference!
