Debuggin a liquid sunshine

[Herr Masel]

Hi, I built the liquid sunshine according to this schem http://www.subdecay.com/images/schemlsv2.gif and a perf layout I created:


The bypass signal works, but there is a loud humming sound instead of a nice creamy overdrive  .
The voltages are:

Q1 G: 0
    S: 1.92
    D: 9.18

Q2 G: 3.12
    S: 2.51
    D: 4.66

Q3 G: 0
    S: 2.6
    D: 4.9

I built the pedal according to the changes made in the schem in yellow and red. The only change I made was I used a polarized cap on the source of Q3, connected the minus to ground. And it doesn't show on the layout but I shorted legs 2 and 3 on both trimpots. One last thing is that the layout is wrong for the transistor's pinouts, I changed it as I was working and double and triple checked.

Thanks in advance guys.

[Schappy]

Use an audio probe.

[Herr Masel]

Ok audio probe is telling me that the problem is at Q2. There is a clean signal on the gate and source (pot2 gets the clean signal on lug3, lug2 has no sound, but it is going through the .22 cap to ground so I guess it shouldn't have any right?). There is no sound on the drain though, nor at or at any point past the .022 cap connected to it.

I've measured all the pots, replaced two of them.. I guess something is going wrong at the drain of Q2, also because Q3's gate isn't getting any voltage.. Happy to hear any thoughts.

[Herr Masel]

I measured the voltages again, after changing a pot or two, Q1 is the same, Q2 has 0 on the gate and the drain won't bias with the trimpot, it's stuck on 8.2.
Q3 is being very wierd, on moment I can bias the drain to 4.5v and the gate has 1.9v and the next it is stuck on  8.2v with 0v on the gate... Could this voltage oscialltion be caused from wiring the trimpots wrong? I shorted lugs 2 and 3, while lug 1 connects to the drain of the FETs. Is there a mistake?

[Herr Masel]

No? I could really use an opinion..

[ckyvick]

Pinout information, this might help
http://en.wikipedia.org/wiki/File:JFET_N-dep_symbol.svg
http://www.datasheetarchive.com/pdf-datasheets/Datasheets-112/DSAP0049344.html

[Herr Masel]

I checked pinouts, they are correct. I forgot to mention after changing the pot and checking with the audio probe again the signal passes Q2 (though hardly distorted) but dies at the node of C4 and R5, right after it.
Sorry to keep bumping this, it's a little frustrating..