Silicon fuzz face hiss
Hi, Just finished a silicon fuzz face, I used two 2n3904 hfe around 210 for both. Biased q2c lowering the colector resistor at 5.2 volts, q1c is at 1.45, with stock 33k resistor, the pedal works fine, but unlike my Ge FF, the more I turn down the guitar volume the more hiss (not buzz or hum) I have, especially when I turn down the volume down to zero. My Ge FF is more hissy in general but the hiss doesn't vary with my guitar volume, and when turn down to zero the hiss stops.
Any ideas? Thanks!
Any ideas? Thanks!
- bajaman
- Old Solderhand
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stick a 100 ohm resistor in series with the dc supply and drop a 220 uf capacitor off the circuit side to ground
be kind to all animals - especially human beings
The filter cap didn't help, but putting a 470 pf cap across colector and base of Q2 seemed to help, it stopped almost completely the hiss at zero volume but not the hiss at lower volumes. At higher volumes it doesn't hiss, (with or without the cap) why is that?
Edit: adding resistance in series at the input also helps, between 4 and 6k but I don't like how it changes the sound.
Edit: adding resistance in series at the input also helps, between 4 and 6k but I don't like how it changes the sound.
- Manfred
- Tube Twister
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Sometimes the germanium transistor itself has a high self noise, the exchange of the transistor can solve this problem.
A bad transistor can be found by cooling it down with an icing spray, if the noise decreases noticeably in the cold state.
A bad transistor can be found by cooling it down with an icing spray, if the noise decreases noticeably in the cold state.