Carbon black fuzz top knob not working

[Fuzz Wizard]

Hello, the other day I built the carbon black fuzz, and weirdly the top control isn’t doing anything. There’s virtually no low end at all, and it sounds very shrill. It doesn’t sound anything like any of the demos of the black ash I’ve found on youtube. I’ve got Q3 biased to 4.5v and R6 is 46.8k ohms, the lowest value that I could find. I tried reflowing the B25k pot, which measures almost exactly 25k but that didn’t seem to help. Any suggestions on what to try?

 

[Feral Feline]

Maybe post better resolution photos?


R6's southern pad looks devoid of solder, it supplies VCC to Q2's collector, but perhaps that's just shadow and it's soldered fine.

Maybe a transistor got cooked during soldering, maybe... I don't really know.


One things for sure, your op-amp isn't soldered in correctly.

 

[Fuzz Wizard]

Maybe post better resolution photos?


R6's southern pad looks devoid of solder, it supplies VCC to Q2's collector, but perhaps that's just shadow and it's soldered fine.

Maybe a transistor got cooked during soldering, maybe... I don't really know.


One things for sure, your op-amp isn't soldered in correctly.

Everything is soldered correctly, the shadow just made it look bad. The emitters are reading 7.63, 1.5, and 4.5v respectively.