Fuzz Face question Difference between the .1uf and the .01uf

[Skreddy]

My first Fuzz Face project had both.  The input cap has a much more dramatic effect on the fuzz tone, going from woolly, woofy/gnarly to tight and lean.  The emitter cap theoretically does the same thing, but in practice it affects the low-end content of the output more directly than it controls the fuzziness; so I would almost call a variable emitter cap a "bass" control.

[Skreddy]

*dupe post

[Solidhex]

Yo

  I've pretty much settled on the 2.2uf/ .047 setup. The 4.7uf will give more "squash" on low notes I've experienced. I try to balance between getting a good amount of gain/ low end and top end fuzz texture. Again amp/guitar setup plays such a big part.

--Brad

[drewl]

After opening it up I had a .022 on the input and a .01 on the output on one of my FF clones which was still too bassy-
I lowered the emitter cap to a 1uf and will have to wait until I get home to try it.
It looks good on a scope here at work, but what looks good sometimes sounds horrible.
This work thing really gets in the way....either that or I should just keep a guitar here in the lab.

[Mark Hammer]

My first Fuzz Face project had both.  The input cap has a much more dramatic effect on the fuzz tone, going from woolly, woofy/gnarly to tight and lean.  The emitter cap theoretically does the same thing, but in practice it affects the low-end content of the output more directly than it controls the fuzziness; so I would almost call a variable emitter cap a "bass" control.

Thanks.  That's very helpful and a nice summary.

I've wondered if it might not be a useful addition to a FF-type circuit to have one pot as stock, with the wiper going to the emitter-bypass cap, but a second pot inserted between the wiper and 2 different bypass caps.  The wiper of the 2nd pot is tied to the wiper of the first, such that the two legs of the 2nd pot provide a fixed resistance that can be distributed across two different-value caps.  So, if pot 'A' is 1k, and pot 'B' is 500R, I could set pot A so that the wiper is 200R away from the emitter, and set pot B such that 400R was in series with a 47uf bypass cap and 100R was in series with a 2u2 bypass cap.  And so on.

[Skreddy]

My first Fuzz Face project had both.  The input cap has a much more dramatic effect on the fuzz tone, going from woolly, woofy/gnarly to tight and lean.  The emitter cap theoretically does the same thing, but in practice it affects the low-end content of the output more directly than it controls the fuzziness; so I would almost call a variable emitter cap a "bass" control.

Thanks.  That's very helpful and a nice summary.

I've wondered if it might not be a useful addition to a FF-type circuit to have one pot as stock, with the wiper going to the emitter-bypass cap, but a second pot inserted between the wiper and 2 different bypass caps.  The wiper of the 2nd pot is tied to the wiper of the first, such that the two legs of the 2nd pot provide a fixed resistance that can be distributed across two different-value caps.  So, if pot 'A' is 1k, and pot 'B' is 500R, I could set pot A so that the wiper is 200R away from the emitter, and set pot B such that 400R was in series with a 47uf bypass cap and 100R was in series with a 2u2 bypass cap.  And so on.

Probably better just to set a variable resistance in series with the larger cap and leave the smaller one always in parallel; otherwise, you'll always get quieter/cleaner in the middle of the sweep and louder/fuzzier at either end.

[jimbob]

I think Ill add a switch to choose between a .1 and a .01 for this Fuzz face. Im making several kinds that will vary from standard FF values but with bc108 a/b, matched smallbear  all american, ect... I AM IN SEARCH. I AM ON A JOURNEY.

[drewl]

Well putting a 1uf on the gain pot seemed to really do the trick for me.
It's still got plenty of fuzz, but a more even distortion tone and not overly bassy.
My problem is I was tweaking different things on two different builds, so since I have the one sounding great, I'll have to set up the other the same way.
Both of these have pots on both of  the transistor collectors, so there was alot of tweaking going on.

[joegagan]

All the old-school pedals, and the FF is a perfect example were voiced to compensate for tone-suck. When you'd put a FF in the signal path you'd have to adjust the tone controls on the amp to offset the tone suck. So the FF was voiced to sound good on an amp that had the treble turned up and the bass turned down.  Now, when you build a full bypass version, there is no tone-suck so the pedal is too boomy and bassy.

Expect that pretty much any non-bypass design is going to need tweaked when you convert it to true bypass.

I am astounded that this seems to have never been mentioned before, but it's pretty damn obvious.

Ron

I don't know if this post was a joke or you were just sleepy, but you do know that the Fuzz Face has always been a true-bypass design, right?  (i.e. no tone suck)

What astounds me is why they never put a tone control on the Fuzz Face.  It's not like there wasn't room on the enclosure. 

marc, i think you might be misunderstanding what ron is saying. i think he is referring to tone-suck when the fuzz is switched on

saying that the amp's controls had to be re-adjusted would indicate that the fuzz is on.

i know this has been said before, basically the circuit was low gain enough that a traditional tone control would have lowered output too much. this is why the gt fuzz, then later the dino fuzz had a 3rd gainstage to make up some lost gain.

good info you've posted here marc btw.

[DougH]

I guess I'm "astounded" that there's a 2 page thread on coupling caps. ?!?

Yawn...

[DougH]

Expect that pretty much any non-bypass design is going to need tweaked when you convert it to true bypass.

I am astounded that this seems to have never been mentioned before, but it's pretty damn obvious.

Ron

What makes the difference?

Sometimes I like it bass-heavy, sometimes I don't. That's what blend controls, tweaking, hell, DIY for that matter is all about. Whatever quirkyness there was in the original voicing, for whatever reason, is far outshadowed by differences in personal taste alone.

[John Lyons]

Just wanted to say that I got something out of this thead Doug...yeah...seems simple but sometimes overstating the obvious can click and you get that "oh yeah I guess that is a what that's doing" moment.
I don't remember ever seeing about some of this stuff.
(cap blend/choice on Q2 emitter, skreddy's blend with resistance to balance gain)

John

[DougH]

Hey John,

I was just kidding around in that post. Just riffing off the "astounded" comments.

[Gus]

 Doug's range control or the EQ in
http://www.diystompboxes.com/pedals/gusOverdrive.gif
or the 2.2uf or .68uf cap in the cathode leg of marshall
variations on a standard gain and eq tuning
or........

[DougH]

Cool ideas here:

http://www.diystompboxes.com/wiki/index.php?title=Simplemods#Simple.2C_Easy_Mods.2FTips_.26_Techniques

[John Lyons]

Oh, ok...I see Doug. Always the class clown huh
The wiki simple mods page is a good one. That should be built upon, most of those are from a long while back.
I remember finding that a few years ago and how it was like a gold mine!


Gus...oh yeah, I forgot about that one.
I guess the thing is that sometimes you forget to borrow concept from other places. Like cathode bypass in the amp world.
Your schematics are very appreciated, tweaked beyond the typical "old hat" circuits.

John

[Skreddy]

All the old-school pedals, and the FF is a perfect example were voiced to compensate for tone-suck. When you'd put a FF in the signal path you'd have to adjust the tone controls on the amp to offset the tone suck. So the FF was voiced to sound good on an amp that had the treble turned up and the bass turned down.  Now, when you build a full bypass version, there is no tone-suck so the pedal is too boomy and bassy.

Expect that pretty much any non-bypass design is going to need tweaked when you convert it to true bypass.

I am astounded that this seems to have never been mentioned before, but it's pretty damn obvious.

Ron

I don't know if this post was a joke or you were just sleepy, but you do know that the Fuzz Face has always been a true-bypass design, right?  (i.e. no tone suck)

What astounds me is why they never put a tone control on the Fuzz Face.  It's not like there wasn't room on the enclosure. 

marc, i think you might be misunderstanding what ron is saying. i think he is referring to tone-suck when the fuzz is switched on

saying that the amp's controls had to be re-adjusted would indicate that the fuzz is on.

i know this has been said before, basically the circuit was low gain enough that a traditional tone control would have lowered output too much. this is why the gt fuzz, then later the dino fuzz had a 3rd gainstage to make up some lost gain.

good info you've posted here marc btw.

Thanks, Joe.    Nice to hear from you as always.  I know it's always best to give people the benefit of the doubt.  I still have to honestly disagree about the FF having tone suck when it's in circuit, though.  I mean, what other gain pedal retains so much treble when you roll off the volume of the guitar?  And regarding the need to make up lost gain?  Dude; there's a boatload of gain in the FF.  It's being siphoned off though a mere trickle via that voltage divider (330R/8.2k) at Q2's emitter.  Replace those two resistors with a 10k pot like a Rangemaster (that will be your "volume" pot) and see how much output you have available...

[joegagan]

true, marc, in most scenarios the ff has a lot of gain. i remember how exciting it was to hear how much volume was available by tapping directly off the collector of q2.

but as i mentioned in another thread, sometimes with an already overloaded tube amp, the low and mid heavy ff tone sometimes causes the pedal to cause a perceived drop in volume.

in cases like this adding a third tranny allows a treble boosting effect that simply isn't available in the ff 2 trans circ IME. you can lower the volume of the effect while still having more treble content in the signal than a stock ff is capable of ( due to the fact that you need a low-ish value input cap to make it fuzz out)

always open to hearing different experiences others have had, and also reading the tech notes of those who know much more than i do.

[DougH]

I guess the thing is that sometimes you forget to borrow concept from other places. Like cathode bypass in the amp world.

And a trick I like to play in a cathode-biased p/p class AB amp power section is to use the biggest bypass cap I can get my hands on. On the last amp I used a 220u and the one before that I used 1000uf. Why? It stabilizes the cathode voltage (slowing it down enough for guitar signal transients) and eliminates that squishy bass response you get in a cathode biased amp. The bass response sounds full & tight. You esp notice it on wound strings up around the 12th fret when using the neck pup. (That's the squishiest part of the fingerboard on my guitars.)

Not that it has anything to do with pedals or other class A preamp circuits for that matter... Just an interesting tidbit from the amp world. Kind of counterintuitive to what we usually think about bypass caps- bigger cap = tighter bass. Who'd a thunk it?

Now back to your regularly scheduled Fuzz Face discussion...

[joegagan]

amp talk .

yawn


just KIDDING doug, don't shoot me!