FuzzFace question.

Burstbucker · Status: Offline

FuzzFace question.

fuzzcentral · Status: Offline

Nope If space is a concern, the cheaper 25V Xicon radials work just as well and sound exactly the same. The only difference is that you'll have to get the 20uF as a 22uF, but due to the 10% (?) tolerance, it may very well be 20uF anyhow!

Phillip

tfc · Status: Offline

Phillip is exactly right. the only reasons I get the 20uf-25v atom tva's is they are laying down and it feels retro. But if you get radial 22uf's it will not affect your tone at all. tfc

Burstbucker · Status: Offline

Oh, I forgot to ask if that large .01uF Metallized Polyester output cap(like the one in the original FF) makes any noticeable difference in tone compared to a regular Polyester cap?

Burstbucker · Status: Offline

I should also mention Phillip, that I like the fact that the only thing that you changed on the FF PCB is adding those two sockets for the transistors, I've always socketed any transistors on the various Fuzz and TrebleBooster pedals that I've built.

The thing that I would change on the PCB though is to put a 10k or 20k trim in the place of that 8.2k resistor on Q2's collector since it's so crusial to get that 4.5-5volt sweetspot. Do you always use an 8.2k resistor like that found on the original FuzzFace pedals or do you find out what the proper resistance needs to be to work with a particular pair of transistors, then put that in the place of the 8.2k resistor?

Fret Wire · Status: Offline

"Do you always use an 8.2k resistor like that found on the original FuzzFace pedals or do you find out what the proper resistance needs to be to work with a particular pair of transistors, then put that in the place of the 8.2k resistor?"

Most of us determine the correct resistor and put it in place of the 8k2 resistor. You can certainly use trimmers for the collector of Q1, Q2, and the-out put resistor. Sometimes they can be more noisy and drift, though. I use a fuzz jig that has quick-disconnect pots for all the resistor values, and sockets for the caps. That way I can determine the correct values on the jig, then transfer components to the pedal's actual board. Many times I also use it to bag up matched tranny sets (with their bias resistors) for later building.

Most people adjust Q2's collector to get 4.5-5.5v, and as long as Q1's emitter is at 0.0v, it will sound ok, and they are happy. But there is more than one way to bias a fuzz:

1. Q2's collector only

2. Q1's collector only

3. Q1 & Q2's collector.

All three methods can work, but will behave and sound slightly different. One way will usually sound much better than the other two. If you try the other methods, you'll notice that even if all three ways of biasing yield 4.5v on Q2's collector, the voltages on Q1's collector and base, and Q2's base and emitter will be different. Those voltages are important also.

Recently, Joe Davisson put up a fuzz-biasing calculator on his site. I tried it with some known, good sounding Ge combos using it. The program was slightly off for Ge transistors, and set their Q2 collectors at 5.5v, but the other tranny voltages were spot on. Even with the 5.5v biasing, the tranny combo's still sounded better than a lot of fuzz's. Joes calculator, when set for the 1k fuzz pot, was doing the biasing using Q1's collector resistor only. I think that dumbfounded most people who thought Q2's collector was the only way to bias a FF.

http://diystompboxes.com/sboxforum/viewtopic.php?t=29782&postdays=0&postorder=asc&start=0

-- Edited by Fret Wire at 11:28, 2005-02-26

-- Edited by Fret Wire at 11:29, 2005-02-26

-- Edited by Fret Wire at 14:35, 2005-02-26

fuzzcentral · Status: Offline

quote:
Originally posted by: Burstbucker
"Oh, I forgot to ask if that large .01uF Metallized Polyester output cap(like the one in the original FF) makes any noticeable difference in tone compared to a regular Polyester cap? "

Barely at all. If you were dealing with a more complex circuit with more stages, then I would use metal film capacitors throughout. I personally like the smaller yellow AVX boxed metal film capacitors that Mouser now sells. They're even smaller than the "greenies."

In the Fuzz Face the different properties of a single metal film capacitor won't be noticeable. A regular polyester film cap will work fine.

Phillip

-- Edited by fuzzcentral at 14:04, 2005-02-26

Burstbucker · Status: Offline

Many thanks guys!

That's a lot of good info there.

guitar_199 · Status: Offline

Phillip,

I am always interested in the biasing of transistors in these Fuzz Faces. My first one didn't really work too well....the second one.... since I bought a pair of transistors rather than trying to hand select them myself.......and used the recommended resistor values .....was MUCH better.

In another message you said:

> Most people adjust Q2's collector to get 4.5-5.5v, and as long as Q1's emitter is at
> 0.0v, it will sound ok, and they are happy. But there is more than one way to bias
> a fuzz:

I just looked to refresh my memory.......Q1 emitter is tied to ground and had BETTER be 0.0v.

Could you clarify this for me? I genuinely am trying to understand and this just threw me a curve ball......

Thank you ..... I appreciate any effort spent in replying to this.

Bob

fuzzcentral · Status: Offline

Hmm that was Fretwire that typed that message a little ways up the page.

Q1s emitter should always be 0V since it's tied directly to ground.

Phillip

Fret Wire · Status: Offline

Yes, Q1's emitter should always be a 0v. You've read too far into what I said. When Q1's emitter is at 0v, it's a pretty good indicator that you've got the transistor pinout right, and haven't made any soldering or component errors. It's one of the voltages you look for when debugging or checking a fuzz.

So, another way to put what I said is:

> Most people adjust Q2's collector to get 4.5-5.5v, and as long as they've soldered and wired the pedal properly, it will sound ok, and they are happy. But there is more than one way to bias a fuzz:

Sorry if the original way I typed it caused any confusion.

guitar_199 · Status: Offline

I understand completely and see what you were saying.

That said..... what are you generally looking for in biasing a Q1?