SOLVED Carbon Black (NO) fuzz


New member
So beginner builder here.
built a carbon black fuzz and can get sound threw but it’s clean sound.
the volume pot turns it up and down, and sound stops when I take out the battery.
so that means it’s going threw the circuit correct???

is it clean because I am using the wrong transistors? Generic npn silicon types with varying hfes, not exactly sure, ones I checked varied from 70-150. Unless I am measuring them wrong.

Any tips or ideas why there is no fuzz??? Is it the transistors?? I have them socketed and replaced them with a series of others.
Can I use PNP transistors if I put them in the same emitter/base/collector orientation? Seemed to produce sound if I did this with a few I tried. All had a clean sound, no fuzz or distortion.

I even used some germanium p416bs just to test it and it made sound, that was a little more fuzzy but basically clean still.

should I order the specific transistors for this build, always read transistors could be swapped out for the most part and sound similar, but different… thought I could get by with some bulk NOS ones off eBay, test a bunch, and use the good ones. Figuring I might have to switch more and test more to get a better sounding fuzz. But thought it would at least be fuzzy a bit. There ain’t any fuzz to this thing now.

Should I test more transistors to get a better HFE range closer to the ones they call for.

thanks for you thoughts and tips on this.

I did not test components which were bought from pedals parts and tayda. Only transistors were eBay specials. But I tested them with my limited experience and seemed to get working ratings.


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Well-known member
Are you using the transistors that the build calls for? Or just ones with equivalent hfe? If the latter, make sure the pinouts match.


New member
Are you using the transistors that the build calls for? Or just ones with equivalent hfe? If the latter, make sure the pinouts match.
Just double checked. Same pin outs, that’s the e/c/b correct?? If so the are same. Although I think the gain is lower than what’s called for.


New member
Can you post pictures that include your wiring?
Not the cleanest wiring job, but everything should be connected good enough to flow current.
no switch connected yet. I did the same wiring for my el sol which works fine.
the pots seem to adjust the sound tone and volume, but always a clean sound no fuzz.


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Well-known member
I asked about wiring since you’re having trouble with two builds. I’d recommend going over the solder joints as a start.


Active member
You can’t straight sub a PNP for an NPN. Current travels opposite of a NPN and requires a center positive power supply. Think of any classic fuzz circuit with Germanium transistors. Unsure since I have not built one myself, but is the trimpot for biasing the transistors, have you tried fiddling with that?
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New member
I will check the solder joints tomorrow as it’s already late here and my son fell asleep in the living room where I have my stuff. So I can’t work on it now. Still making a dedicated space in the garage for my new hobby.
the pots seem to work at least the sound changes when I turn them. I can turn volume knob all the way down and so goes the volume. The tone seems to change when I turn other pot. Trim also seems to adjust the sound when turned.
Tried npn silicons at first, just some randoms that I thought matched somewhat close to the gain needed.
After that I tried the germanium putting them to the corresponding e/c/b spots. When I did get sound with the ones I tried it was still clean. Put back in the npn silicons now and still clean sound.

Maybe I am mistaken though about the transistor though? would using a pnp in place of an npn cause it to be clean like this, or just not work at all????
If I remove one transistor the sound stops. Or put one in the wrong way, no sound.

Which brings me to a related question on transistors.
I have also just bread boarded a basic fuzz face circuit with germanium trannies designed. (Did this instead of working on my other problems, thought maybe working step by step on a breadboard I could learn more about the circuits, along with getting some fuzz finally from my Russian trannies I found of eBay.) But I Also can’t get any fuzz from this even after switching out many transistors. Same deal where trim pots will have noticeable effect on the sound, but NO fuzz.

A main question here applying to both builds is, will a transistor with the wrong specs work to create a clean sound but won’t produce the fuzz. Like if it has too much leakage and not enough gain? so will not enough gain or too much cause it to be clean??
Will a bad transistor still let sound pass but not work to create the fuzz?? I probably tried 3-4 different pairs of transistors for my breadboard fuzz face and all made clean sound. So could the trannies be bad then?? Or do bad trannies just not work at all???

Or is it more suspect that their is a bad joint that is blocking the circuit somewhere? Like if a key resistor or capacitor wasn’t fully soldered, and so the pots would still work, but leave it with no fuzz??

From what I have read the transistors create the fuzz, and so my mind just went there first.

Wish I had more time to tinker with this stuff, sorry for slow responses/testing.

Thanks all.


New member
Hey guys it was the transistors!

I tried some more eBay generics. Some old NOS with gold pins. I didn’t even check these guess yet, not like I was probably checking them right before….
But threw them in one way and it was a just the clean sound again.
Threw them in the other way and it WORKED!!!!
Sounds awesome. Probably better because it actually worked. But still actually a pretty nice fuzz. Bias had a large range of sound as well which I liked.

Thanks everyone for your advice.