Less gain and better timbre for GuitarPCB Super Fuzz?

[l8e57kijryhq3]

Hi,

I have a DIY GuitarPCB Supa Fuzz, a schematic can be seen here in its build document: https://guitarpcb.com/wp-content/uploads/2018/06/BD_CT-Supa-Fuzz.pdf

It's a three-transistor fuzz with 2 ge diodes. Transistors used in this build are 2N5089's, NPN Si transistors with hFE specified between 200 and 450. The sound of the box is quite harsh, even spikey and shrill, and it has too much gain for my taste. Doesn't clean up with volume knob.

What do you think, would switching to another Si transistor with less gain, like 2N3904 tame it down a bit, and would it need some re-biasing of the circuit? Or could I swap in some Ge trasistors to make it more mid focused and not that harsh? I don't really understand how the box clips the signal, so I'm at sea with it. I could just look into another pedals for sure, but this sounds quite fine when it sounds fine.

I'm a total noob, but this is I could do - the transistors are installed in SIP sockets, so I don't even need to solder them.

What I've read is that the Q1 before the gain stage basically buffers the signal, which means the guitar volume knobs varying impedance doesn't affect the fuzz circuity in the same way than in f.ex. classic two Ge fuzzes, so I'm not sure what to do.

New here btw., nice forum you have.

[Mark Hammer]

It appears to be an attempt at a more sizzling Sola Supa Tonebender.  That in turn is essentially a Big Muff Pi with no clipping diodes for Q2 (as would be the case for a BMP).  The culprit here seems to be D5/D6, which are not normally found in either the Sola pedal or the BMP.  I recommend lifting their ground connection and seeing if that does what you want.  There is no real need to change the gain structure...yet.   If taking those additional diodes out of the picture doesn't do what you need, THEN we'll talk changing the gain.

[bluebunny]

New here btw., nice forum you have.

Yes, we do.  Glad to have you join us. 

[Mark Hammer]

I'll echo that.

NOW you're in trouble! 

[pinkjimiphoton]

a superfuzz style circuit doesn't react to volume knob changes much. if ya want that kind of effect, i'd suggest guitarpcb's dsotm fuzz instead. it is one of the better luna fuzz variants out there and i use it myself on my live board.

the superfuzz you're better off to embrace for what it is. its NEVER gonna NOT be a rude gated kinda fuzztone unfortunately.

you can try low beta q's, hfe 200 or less, but it won't really help much, will just make it kinda anemic sounding sadly.

these kinda fuzzes just sound like shit. thats their main attraction. if ya got it going into a wall of hiwatts with an sg and your guitar barely on, maybe it might seem a little more toneful, but...

a superfuzz circuit is a superfuzz. i was gonna pull the trigger on this over the weekend, but its not a tone i personally enjoy or use so i passed. usually i buy everything barry puts out there.

taking the clipping diodes mark mentions out will make it cleaner and louder, but i don't think you'll necessarily like THAT tone, either... it will remove some compression at least.

try this... if ya have a ge diode, put it in parallel with either d3 or d4. this should work as a bit of a noisegate, and tame the fuzz down a bit while keeping its essential character.

you'll either love it or hate it. good luck man, and welcome to the best addiction of all the monkeys who ever danced on my head

[Mark Hammer]

Not to rain on your parade Jimi, or critique your commentary about the actual Superfuzz circuit, but the OP is not actually dealing with a Univox Superfuzz circuit.  It's a Colorsound (I mistakenly said Sola) Supa Tonebender.

[pinkjimiphoton]

ahhhh, my bad.

in the demo from barry is sounded pretty much like my old orange and blue superfuzz. personally not my cup of tea, so i didn't look up the circuit.

carry on!!

[Mark Hammer]

Nah, their bad for calling a Supa-Fuzz.

I don't know why they insisted on adding the second pair of diodes.  While I hesitate to call it "magic", one of the things that gave/gives the BMP its characteristic "violin" sound is the use of two consecutive clipping stages.  Remember that the diodes that do the clipping in Q2 also serve as a crude sort of limiter/compressor.  When they are removed, the dynamic range of the output of Q2 is increased somewhat, such that it hits Q3 a little harder.  I made a unit for myself with a TS-808, BMP and FY-2, each having a pair of 3-way toggles to change some parameters.  One of the BMP toggles selects the Supa-Tonebender option.  I was expecting something maybe a bit smoother, but it turned out to be a little harsher.  That said, should one be building either a Supa or a BMP, implementing a toggle to select between the two isn't a bad option to consider.  It's easy to do.

[pinkjimiphoton]

https://www.youtube.com/watch?v=lwUYGK2X40E

sounds like a superfuzz to me

personally, i prefer very low gain q's in a big muff. much more liquid and violin like, with the ridiculous creamy sustain.
i agree with mark about the diodes either way. their main function is to tame it down by compressing the signal.

frankly, i don't really care for the diode clipper distortion sound much anymore...
kills dynamics too much, makes stuff too squashed for my ear.
i have never understood why people said adding a diode clipper would make stuff louder.
it doesn't, if anything, you lose gain... and if ya run enough diodes in series to make up for this drop, then they don't clip, so,,, ..... kinda useless. in some circuits they can sound great, but i pretty much stopped messing with 'em a couple years ago. if i use diode clipping now, its usually a fusion of GE and led, and usually only one half of the wave.

watch the video... seems to me to sum up the problems the op was asking about, and to me? sounds like a superfuzz. i've built a few for friends, but never really cared for that kinda fuzztone too much.

ymmv and should!

on a side note, looks like they gave up on the "photon phuzz"... MY photon phuzz was a completely different circuit, this was one of the stupid simple overdrive circuits.

that said, i love barry and guitarpcb, great little outfit!