+bias voltage slowly rising

[stevens]

hi,
i'm trying to set the bias voltage (haven't installed the op amp yet) but the positive bias seems to steadily increase by about 0.1v every two seconds. The negative bias remains constant, which makes me wonder if there's something wrong.
At first, before I noticed it was increasing, I had R25 maxed out, yielding 17v. Then when I noticed it was changing, I turned it back down a bit and watched it steadily increase for a few minutes. Is there something wrong here?

[stevens]

i should also mention that when i first measured with the pots fully CCW, one of them was 14v and the other was around 12v. I'm not sure if that's way off or close enough, but I did check all the things in step 33, and they're all fine.

[stevens]

i checked that whole part of the circuit for shorts, and also that everything is connected to what it's supposed to be, and all the right parts are in the right places and installed the right way.

SO should I try replacing the regulator? Or could it possibly be one of the other parts that are close to it? Is there a way to test without pulling anything out?

[tpryan]

Does it stabilize at some voltage eventually?

Are you absolutely sure that C4 and C12 are installed the right way round?

[stevens]

D'oh! I had C12 in backwards!
I fixed my mistake, it's working now, and it sounds amazing!

Tim, thank you for your help and for putting together such a great kit! Now I'm off to do the other modules!