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BC108 fuzzface mods

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5/16/1999 7:49 PM

BC108 fuzzface mods

I came upon one of these by "accident", but I am glad I did. I built this using BC108 that have hfe's of 138 and 140. R.G. inspired me to try and get a good sound from this thing. Mod 1 is to use a 47uf cap on the fuzz pot. This gave better low end. Mod 2 was a 2k fuzz pot which gave more, and smoother fuzz than the 1K. Mod 3 is a 27K resistor from the 9 volt line to the base of Q2. I think I ran out of 33k last summer and just stuck this in. Now the wierd one....I thought I was adding a 5.6K resistor to the 10K resistor between the .1uf cap and the collector of Q2. But, I mistakenly put it on emitter to base. I used a pot set up as a rheostat to find the best sound, then stuck in the resistor. This seemed to really bias up the circuit for the most even tone. The sound compares quite well with my NKT275 equipped fuzzface clone that I use all the time. About the only huge difference is that the BC108 circuit picks up a radio station when the guitar volume is off. Mark

5/16/1999 8:37 PM
R.G.	Good tinkering!! The radio stations can be cured with small (under 100pf) collector to base capacitors or similar capacitors from base to ground.

5/17/1999 6:01 PM
marrk	Thanks for the tips! I'll give 'em a try. I have some small polystyrene caps laying around from a ripped up tape deck Mark

5/17/1999 7:45 AM
Gus	mark look at my schematics posted at aron site. Also look at justins site for the Diaz square face I traced out. I have been working good sounding silicon dist for awhile now. Gus

5/17/1999 8:41 AM
R.G.	Gus - I traced out the Square Face a long time ago. UGH! It sounded too bad to even consider. Unless you can work miracles, there are other, better places to start.

5/17/1999 12:04 PM
Gus	R.G. I agree that the Square Face does not sound very good. My unstated point was the use of the 2k gain pot. I can not believe SRV used one of the square faces. Gus

5/17/1999 12:43 PM
aron	Re: BC108 fuzzface mods/Diaz Again, "Magic fingers" come into play. My friend who plays with Hiroshima came to Honolulu and I played with him on a gig. He sounded amazing....Great distortion, nice soloing. I asked him what he was using and it was the Diaz Square face. Borrowed amp, just the Square Face into a Rivera combo. Go figure! Aron

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