fuzz face question

[danwelsh]

Hi guys, so I wanna build this ptp fuzz but its pos ground. If I flip the orientation of all caps would it become a neg ground?....or can this be done?

[kothoma]

http://www.muzique.com/lab/fuzzface.htm

[Vallhagen]

kothoma's link gives great info. Play with it!

Another solution is to change transistors (from pnp) to npn, switch orientation for the electrolytic caps and ... change to negative ground. Done.

Cheers

[danwelsh]

So I built this and I'm getting really low output and not much voltage to the collector of my transisitors....I'm getting 9.0 volts at the bottom of the 8.2k resistor and at the other end to the collector it drops to 1.9 volts....do i have to change this value to get more voltage going to the transistor? Also I did change the polarity of the caps, changed to npn and also subbed a 22 uf for the 20 uf cap.

[Vallhagen]

I shall not go too deep into this, as i know theres other guys here that are far better than me to explain everything about this Fuzz Face circuit. But a start hint, if you want to get more into it, RG-s word on it is highly recommended:

http://www.geofex.com/article_folders/fuzzface/fftech.htm

... also; change your title on this thread to include "Fuzz Face", then the knowledge guys finds it easier:)

Cheers

[RobA]

I've got to thank you Dan for asking this question just now and Kothoma for the first reply. I was just getting ready to etch a board for a layout of the Range Master with a charge pump to get the negative rail. I looked at that first link and changed my mind. Tried it on the breadboard and the inversion worked perfectly, so now I can do it point-to-point and bypass all the charge pump issues.

The Keen article at Geofex is a great place to get the details on what to do with the FF. When I was breadboarding the Range Master circuit this time, I replaced the critical resistors with trim pots. I then went through about 20 different not-so-great Ge transistors and all except one were bias-able to a good point. The one had too much hiss at any setting. Some were still better than others, but all except the one sounded good. I haven't been able to get results as good with the plug in and out resistors method before. With the trimmers, I could get set the values close and then dial in the sound. I haven't tried it yet, but this could work well for the FF circuit too.

[danwelsh]

Hey guys....looks like my problem lies with the 470r...it should be 330r when using npn. I'll desolder and try this tomorrow after work. I found that info here for anyone interested http://www.tdpri.com/forum/burnt-fingers-diy-effects/297272-fuzz-face-point-point-diagram.html