Promethium too quiet too dark

Vild

Active member
If I use extra gain and crank up the treble on my amp it's almost like the it is doing things right. Still can get a little chainsaw action. But ultimately it's way too quiet, too dark, and low gain. (Confirmed side by side with an actual hm2 plus with everything dimed it's quieter than dry guitar signal)
I checked component values but I guess I must've missed something or it's an ic/transistor problem.

I'm guessing that q2 is supposed to measure different but I don't know. Which if that's acting wrong and isn't putting out enough volume to drive the rest of the circuit properly that seems to make sense. But I don't really know. I'll try to audio probe in the morning and see where volume drops I suppose?
If anyone finds anything/has any advice etc.. I would really appreciate it. I built this for a friend and it's the first pedal I've made that's messed up in a while so it's stressing me out a bit.

Source voltage measures 9.55
From left to right
Q1; 9.27, 5.47, 2.28
Q2; 0, .6, 4.34
Q3; 8.43, 7.51, 3.96
Q4; 3.27, 2.78, 9.28

Ic1; (top)
P1 4.58
P2 4.58
P3 4.57
P4 0
P5 3.96
P6 3.97
P7 3.97
P8 9.28

Ic3; (middle)
P1 4.58
P2 4.58
P3 4.15
P4 0
P5 4.21
P6 4.58
P7 4.58
P8 9.28

Ic2; (bottom)
P1 4.58
P2 4.58
P3 4.27
P4 0
P5 4.15
P6 4.58
P7 4.58
P8 9.28
 

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Last edited:
One issue I had when building a HM-2 inspired circuit was that I wasn't paying attention and mixed up the PNP, and NPN transistors for Q2, and Q3. Worth double checking.

If that is correct, I would measure components around Q2, trying to map out if the R7,R8, and R9 are correct. Measuring in circuit is always tricky, but you can find things like short to ground, or broken connections. Just follow the schematic and try to figure out which end is which for each component.
 
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