Anyone Else Built Gus Smalley's Face Fuzz?

Started by fuzzymuff, March 16, 2013, 12:03:30 AM

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fuzzymuff

Just got done building it today.  Its calls for a pair of 2N3904 transistors.  The ones installed have about 350 hfe and has a saturated fuzz.  It does not seem to clean up like the traditional fuzz face when lowering the guitar volume.  For those who have built this fuzz face variant, what transistors did you use and what hfe?
Also, what I noticed is that when I set the Q2C at 4.5, it seems to sound gated, specially when lowering the guitar volume for clean tone.

fuzzymuff

#1
Hello Gus,

Here are the voltages.  When set the external bias 5k linear pot about 11:00, what sounds good to me, Q1 E .08v, B .69v, C 1.39v, Q2 E.80v, B 1.39v, C 7.13v.  When bias set to max, bias control counter clockwise to 7:00, Q1 E .08, B .70, C 1.39, Q2 E .81, B .79, C 7.80.  When set to min bias, clockwise to 5:00, Q1 E .08, B .69, C 1.43, Q2 E .80, B 1.43, C 1.14.

I'm also experiencing noise, like a static hum noise when the veroboard is placed right over the fuzz control.  The source voltage is 9.43 for one spot wall wart.


Thanks Gus.  Looking forward to your reply.  I also made the output caps, 100nf and 1uf switchable and I found the 100nf seems to tighten the bass response.  Its very subtle, but can hear it more when the fuzz control is set at max.  Speaking of the fuzz control, it seems to bunch up from setting 4:00 to 5:00.  A dramatic fuzz increase from 4:00 to 5:00 and increase in hum, but when turning the fuzz below 4:00 it cleans up dramatically.

My Vero Layout of Gus Smalley Fuzz Face



My build of this fuzz:


fuzzymuff

Here is an updated version, JH2 Mod.  This one sounds really good!!




bluesdevil

Just a note:
Those 2n3904's you mentioned with 350hfe (from Tayda?) are more than double the hfe of the older 2n3904's. You might try to socket those trannies (did I just type that?!) and try lower gain ones like PN22222's that have gains around 150hfe to see if that cures the super saturation if that's not what you're going for.
"I like the box caps because when I'm done populating the board it looks like a little city....and I'm the Mayor!" - armdnrdy

fuzzymuff

Quote from: bluesdevil on March 18, 2013, 01:07:53 AM
Just a note:
Those 2n3904's you mentioned with 350hfe (from Tayda?) are more than double the hfe of the older 2n3904's. You might try to socket those trannies (did I just type that?!) and try lower gain ones like PN22222's that have gains around 150hfe to see if that cures the super saturation if that's not what you're going for.


Yea, those 2n3904s were from Tayda.  I got a couple of BC108B that were below 200 hfe and it solved the problems I had previously.  Thanks.