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Re: Gus Smalley: 3 Trans Fuzz Questions

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5/7/1999 6:06 PM

Re: Gus Smalley: 3 Trans Fuzz Questions

Thanks, Gus. I tried reducing C_in but it didn't have much effect on the sound. As you suggested, I went after the 0.022uF cap instead of C_in and had much better results. I think that I may use a rotary switch there -- I like the full sound for leads but a "lighter" sound for rhythms.

I've looked over the circuit and I understand every component except one: the 47k feedback resistor from Q3's emitter to Q2's base. From what I can tell, Q2 inverts the signal since Q3's input is tapped from Q2's collector. However, the 47k feedback resistor is connected to Q3's emitter where the signal would not be inverted. So: Q2 inverts the signal but Q3 (as far as the 47k feedback resistor is concerned) doesn't invert the signal. In other words, it looks to me like the 47k resistor is sending an inverted version of the signal back to Q2's base.

Can you explain this to me?

5/11/1999 4:42 PM
Joe Fuzz	Theory Question My question seems to have slipped through the cracks so I'll throw it open to all takers. See the proceeding post for more detail but basically: What's with the 47k feedback resistor from Q3's emitter to Q2's base in the 3TF circuit? Thanks!

5/11/1999 10:19 PM
aron	Joe, Read the technology of the Fuzz Face at: http://www.eden.com/~keen/fffram.htm Then look at: http://www.geocities.com/CollegePark/Library/1355/gusFuzzFace.gif hehehehe! Aron

5/12/1999 7:30 AM

the 47k with the 10k into the base help set the gain (47/10 x gain of 3rd tran stage). When I built the circuit I made that resistor a 33k in series with a 100k pot(33k to 133k) I like the sound at about 47k to my ears if you set it at 100k the bass does not sound good. All the resistors were changed one at a time and changes noted in a notebook same with the caps. the first collector resistor 10k with a 100k pot. emitter r 0 to 100 ohms etc. The basic schematic is nothing new the only thing is that it is tuned to my ear using fender type amps(notes given to help tune the circuit on the schematic). If anyone builds please give feedback.

5/12/1999 11:53 AM
aron	Gus, Do you use trimmers when substituting resistors or do you simply swap them by hand in a proto board? Thanks! Aron

5/12/1999 1:04 PM
Gus	I used trimmers. FWIW I do not like protoboard with all the stray cap etc. I build with perfboard no sockets I also single point gnd and single point power my effects with wirewrap wire I also use very short wire lenghts and very rarely have any osc problems.

5/12/1999 11:01 PM
aron	Cool! Thanks Gus! Aron

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