Fuzz Face NPN Silicone, Newb Help

[msurdin]

I want to build the NPN Silicone Fuzz Face. I Have been looking at the layout and parts from GGG ( Link http://generalguitargadgets.com/diagrams/fuzzface_lo_nn.gif)
On the site it said it still has part values for a germanium fuzz. I want to use BC108 work a likes from small bear to do the job.
From what I have read on GGG is you need to change R4 from 470 ohms to 330 ohms. Would this be the only change?

Thanks for your help!

Matt

[tcobretti]

There are many, many, many versions of the Silicon FF circuit.  If you search the archives for "Si FF" you'll find gobs of info.

Here are some links:
http://geofex.com/Article_Folders/fuzzface/fffram.htm
http://fuzzcentral.ssguitar.com/axisface.php
http://aronnelson.com/gallery/albums/album161/FF_PNP_Socket_Friendly_Vero.gif
http://aronnelson.com/gallery/albums/album160/RM_Stone_Fuzz.gif
http://www.diystompboxes.com/pedals/gusFuzzFace.gif

Read the first three links, study the schems, figure out what mods you want to try, and go for it.

[Jaicen_solo]

Are you looking to build a Si FF just because the transistors are easier to get??  I'm not trying to convince you otherwise, I like a good Si FF as much as the next bloke!  I personally favour using a hybrid silicon and ge fuzz. For NPN, I use 2N3904 and AC127's, and for PNP AC128's & 2N3906's. That way you get good stability, and a fair bit of gain. Low gain Si transistors could be used, but i've not found any that match the sound of the 2N3904 or 3906.
I've also had some really good results using 2N7000 Mosfets in there, they' have a really METAL kind of fuzz sound, but I guess it's all horses for courses.

[petemoore]

  FTFF'er [first time fuzz 'facer]?
  You [for best initial and long term tweeking results] wanna know stuff.
  Geo is complex, but work around the tuff parts, attack a tuff part, one at a time, I had to do 'subcontextual' research to make that work...ie definition of terms, studying component functions etc.
  Very flexibly moddable circuit, can be relative clean boost to super fuzzy.
  My first board that I built with:
  trimpot for Q2CR [Q1CR~?..]
  socket for input and output cap, ~100k and ~330R
  ...solidly on perfboard [I use 16pin IC socket layout, very sturdy built]..but I dunno where to see it, I'll see if I got a diagram in photobucket...
  Makes nice 'permanent-moddable' FF testboard, bias can be reset after Q swaps, then tweeks can be done around those Q choices.
  This frees up the breadboard [I still tweek FF's..trying out transistors 'n stuff...still...been five long Yea's...still tweekin' on that FF testboard...or use a breadboard.
  The volume control on the guitar functions like a gain control, the FF Will sound different to a relative large degree depending on X factors like 'what's the source' [HB, SC pickups or other] and 'whats the output going in'...the FF is known for it's ''what 'come's-in come's-out-as'' type effect, highly variable...moddable...
  Also see '3 transistor Fuzz' and 'Rocket'..I'm about to finally glue in the transistors chosen for the Rocket...I had to pop the bottom off and put Q1 back in it yesterday...lol, sounded great on playback, critical to the recorded performance, it was driving a 50w JCM amp.
  In fact, now that I'm thinking of it, I'll go do that right now.

[tcobretti]

Yeah, you can make the basic FF circuit into just about anything you want.  I've gotten overdriveish tones with low gain Si transistors and a low value feedback resistor, I've done the metallic thing with the 2N7000s (I need to try that again, it's been a while), and there's always the classic Ge FF.

Remember, because of how different all the Ge transistors were from each other pedals with the exact same type of Ge transistors can sound very different.  So there really is no textbook Ge FF sound.  I will say that there are some Si designs out there that get VERY close to the Ge FF sound - the two I have linked above, and my own Mondo Fuzz all do a pretty good job.  No it's not exact, but I'm willing to bet that in a Pepsi challenge many of us could not say with absolute certainty which was Ge. 

Because Si transistors are brighter, they arguably sound "fuzzier" than Ge.  So if you want a nasty fuzzy 60s pedal, Si might be the way to go.  If you want a more beefy Hendrix tone, you would want Ge or one of the Si based Ge clones listed above.

[petemoore]

  PNP Pos. Gnd. FF
  or
  NPN Neg. Gnd. FF
  These two power supply scheme FF's work.
  The other one I dunno about, often troublesome if you don't know about it [PNP Neg Gnd.].

[Torchy]

My recommendation is for Phillip's Axis Face ... NPN Si Fuzz Face with some tweaks.

http://fuzzcentral.ssguitar.com/axisface.php

You can use 2xBC108s or use the transistors Phillip specifies.

[msurdin]

I really want to make something close to the analog man sun face with bc108's. I play alot of Pink floyd and I know i want the ff with bc108 sound.