switching PNP to NPN in a fuzz

[Michael]

Hi

I have some nice silicon transistors, and i want to try these in a fuzzface (reissue from early 90´s).

Is it correct that reversing the capacitors and battery clip, and of course changing the transistors from PNP to NPN, is all that is needed for this to work? Do i need anything else to be changed? Resistorvalues or?

Michael

[aron]

That should work. Try it.

[MartyMart]

Michael, that's it in a nutshell, Phillip over at "Fuzz Central" usually supplies an "NPN" schematic along with all his
different "PNP" Fuzz circuits.
They work a treat and you can then power them from a normal "Boss" type PSU !!
( I HATE "POSITIVE GROUND" CIRCUITS )

Marty.

[formerMember1]

Michael, i assume you know about rebiasing the pedal after changing transistors. If so, the following is for others that are browsing.


If not, you will probably have to change one of the biasing resistors, and measure the voltage on the collector of Q2.  4.5volts to 5.0volts
works for me, preferably 4.5volts.  I usually change the 8.2K resistor to a 10k trim pot temporarily or permanently. 

  Also if you test the transistors for gain you can use a lower gain in Q1 and higher gain in Q2.  Usually transistors around a pair of 70-130 will give you the best clean rollup via the volume on guitar.  higher gains don't give as much clean up via guitar volume but have a unique sound all there own anyway.  Think JIMI.   

hope i helped someone