Help with fine tuning Fuzz circuit Please

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sonolink

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Feb 15, 2010
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Hi guys!!

I built 2 Fuzz circuits based on the classic Arbiter Fuzz Face. They both sound great BUT they have some noise I'm trying to get rid of. Both circuits are the same, only some components values are adjusted to tune them with the transistors used.

Circuit 01 is using a BC338 as Q1 and a 2N3904 as Q2. It sounds fantastic and has a huge range of colors and textures BUT, hisses all the time. Even when the guitar is unplugged.

Circuit 02 is using 2N3053s. Same as before only there's some high pitched noise and some static instead of hiss.

I tried modding both circuits after reading R.G.Keen and other posts but I can't get rid of those noises. I know that this circuits has an inherent bottom noise but I'd like to try to minimize as much as possible. I've attached schems and audio. The ground noise is mainly due to the circuits being breadboarded.

Circuit 01 schem:

Fuzz 2N3094.jpg

Circuit 01 hiss:
View attachment Fuzz Test 04.wav


Circuit 02 schem:
Fuzz 2N3053.jpg
Circuit 02 high pitched noise:

View attachment Fuzz test 01a.wav



All your ideas and suggestions very welcome as usual.
Thank you for your kind help
Sono
 
Hi guys!!

I built 2 Fuzz circuits based on the classic Arbiter Fuzz Face. They both sound great BUT they have some noise I'm trying to get rid of. Both circuits are the same, only some components values are adjusted to tune them with the transistors used.

Circuit 01 is using a BC338 as Q1 and a 2N3904 as Q2. It sounds fantastic and has a huge range of colors and textures BUT, hisses all the time. Even when the guitar is unplugged.

Circuit 02 is using 2N3053s. Same as before only there's some high pitched noise and some static instead of hiss.

I tried modding both circuits after reading R.G.Keen and other posts but I can't get rid of those noises. I know that this circuits has an inherent bottom noise but I'd like to try to minimize as much as possible. I've attached schems and audio. The ground noise is mainly due to the circuits being breadboarded.

Circuit 01 schem:

View attachment 146759

Circuit 01 hiss:
View attachment 146761


Circuit 02 schem:
View attachment 146758
Circuit 02 high pitched noise:

View attachment 146760



All your ideas and suggestions very welcome as usual.
Thank you for your kind help
Sono
I've built a lot of fuzz pedals (including germanium transistors which are noisier),
but I've never had this kind of accented noise.
Is the circuit on pcb or point-to-point?
Is it shielded in a metal box?
Did you use metal film or carbon film resistors?
Are the capacitors of good quality?
Did you accidentally ground loops?
Is the power supply with a transformer or from the battery (which type of battery matters)?
Is the fuzz fed from the same source as other pedals?
Is it connected to other pedals in front of it?
 
Agreed with micolas suggestions.
Also try shutting off all lights - especially any on dimmers - move away from any noise inducing electronics like monitors.
A Si pedal should be pretty easy to build quiet
 
Is the circuit on pcb or point-to-point?I s it shielded in a metal box?

Right now it's on breadboard

IMG_20250228_192322.jpg

Did you use metal film or carbon film resistors?
Metal film

Are the capacitors of good quality?
They are multilayer ceramic from Mouser

Did you accidentally ground loops?
I'll check but I don't think so


Is the power supply with a transformer or from the battery (which type of battery matters)?
The PSU is Truetone One spot.

17407671623365209749685660695954.jpg



Is it connected to other pedals in front of it?

The only elements present are the guitar, the circuit on breadboard+ PSU and the amp.
Also try shutting off all lights - especially any on dimmers - move away from any noise inducing electronics like monitors.

No lights on except one in the room

Thanks for your help :)
Cheers
Sono
 
@sonolink
You need to shield the circuit in a metal box connected to GND
Ok. I was breadboarding it to adjust several trannies and adjust their bias. I'm very happy with the sound now so I guess I could make a quick vero and box it in a 1590B to check if it's still noisy. I'll do that and report back :)

Thanks a lot for the help

Try powering it with a Duracell battery.

Any reason for it to be a Duracell. Won't a Panasonic do? ;)

Cheers
Sono
 
FWIW I hate Duracells. I call them DuraHell because they often end up leaking and corrode the guts of whatever equipment they are in. Energizers aren't much better.

Ray-O-Vac has been much better for me, but I'm sure other folks on the forum might disagree.

End of topic veer......

Bri
 
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