Another follow-up, in case it comes in handy for someone else…
I’ve been working with MJMP on this. He noticed from the photos I sent to him that a previous owner had replaced some of the original yellow non-polar caps with polarized, and I saw that they had swapped a few opamps. Thankfully the seller provided some of the opamps he had tried, and so I incurred a very minor expense to replace the caps and buy a 417 opamp. Swapping these things did not cure my problem, but it made an improvement.
OD1 does nothing on any voicing or preset.
SS is basically broken. It has very little signal, which I suspect is a residual “background” or “trickle” signal. The chorus doesn’t work, but the tone controls do. Go figure. Raising OD2 does little until 7.5, then the level goes DOWN, until 10.0, when it goes completely silent. Master Gain does nothing. I had forgotten that switching voices deaults the master gain to zero, but there was a very low signal passing through anyway, which is what I had percieved as getting “quiet and muddy” on all voicings and not changing when I went back to the original voicing - because they were all defaulted to zero. Sometimes I’m a dope.
On the clean tube voicing, OD2 does little until around 4.6, then incrementally increases as nearly normal to 6.5. At 7.0, there’s a significant volume jump. The same behaviour is exhibited in tube dist, but that jump is heard as a jump in both volume and gain.
Overall output level is very low.
I’ve sourced and ordered Vactrols, which I hope will address the issue with OD1, and maybe the weird behaviour of OD2. Not sure what to do about the SS voicing.
We’ll get this going, but I have to say MJMP has the patience of a saint. I’ve probably irritated the crap out of him with all my noob questions.