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Hoffman Amps Forum image Author Topic: Fuzz Face change from NPN to PNP Ge?  (Read 7368 times)

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Offline smackoj

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Fuzz Face change from NPN to PNP Ge?
« on: October 31, 2018, 07:17:49 pm »
I picked up a Fuzz Face clone that was reported to be Not Working. I think it was just grounding out of the case lid. It is working but it uses 2 older metal case NPN transistors. I want to try a couple sets of Germanium PNP but not sure of one thing: If I replace the NPNs with PNPs and make sure that the E B and C  connect to the same pts as the leads on the NPNs, can I just reverse the Plus and Minus power connections and it won't fry any of these costly Ge transistors?
Thanks for the help amigos

Offline pdf64

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #1 on: November 01, 2018, 02:45:17 am »
Any polarised caps would need flipping over too.
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Offline smackoj

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #2 on: November 01, 2018, 10:40:45 am »
That makes sense. Thank you.

Offline jojokeo

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #3 on: November 02, 2018, 03:33:00 pm »
Here's a generic NPN FF schem to help.
To steal ideas from one person is plagiarism. To steal from many is research.

Offline smackoj

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #4 on: February 21, 2019, 06:52:14 am »
Late night, early morning follow up; thx for the help amigos.  Here's the long and 'short' of this pedal. It was indeed 'shorting' out on the metal case lid so that got fixed post haste. The sound of the 2 orig. vintage metal case NPNs was lame. I went thru a stash of older BJTs and found a single NPN metal case. I put it in with one orig. and it sounded great IMO. I don't use fuzz on guitars so I'm not a seasoned critic but I sold it to a local guitar player and he called me the next day wondering if I had another identical FF in case this one looses it's mind. So, just saying thx again and I did not need to flip it to PNP to get a great sound.
« Last Edit: February 21, 2019, 06:55:16 am by smackoj »

Offline jojokeo

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #5 on: February 21, 2019, 04:23:10 pm »
Not surprising to hear that it didn’t sound to your liking. But wondering exactly what it was? Splatty &/or buzzy (bias/voltage), dull & nasally (typical with many germs), something else?


I am always curious about comments & experiences because it’s always a mixed bag with germs and even in combos.


Thanks for the update OJ, it’s always nice to see & hear follow-ups.
To steal ideas from one person is plagiarism. To steal from many is research.

Offline smackoj

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Re: Fuzz Face change from NPN to PNP Ge?
« Reply #6 on: February 21, 2019, 08:06:10 pm »
Ola Cmdr. JoJo;  I had not visited this site for such a long time that I cannot member a whole lot about the FF. I would have to say that with the 2 orig Qs it sounded like something from a dime store. Not much tone and what there was had the dreaded thin, nasal similarity. I am pretty sure they were not germs though. I think they were early (60s) non-germs. Very small with chrome looking metal caps. The one I found in the parts box was something the package said was used in early TVs. I looked it up on-line and it said could be used as a fairly low gain amp (60 hfe) so I pushed it in the quick change pad and it sounded great. At least to me and the dude who bought it there was a much more musical growl. Good to hear from you amigo.
JD

 


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