Subwoofer Died

KitCarlson said

That D108 might be a zener, to get the right reverse voltage for regulation use exact replacement. I am using my phone to read schematic, so not sure.
Things to check is the boost supply for the D-amp. It will be bi-polar, that means a +, and - outputs around 30V. Could be more or less depending on power rating, the +, and - voltages should match.

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Right you are, saw that for myself in a printed version of the schematic today. The source should be higher than 15vdc by a bit you are probably pretty close with the 30vdc. I'm going to change out a couple of zeners first, we lifted one end of D108 just to be sure it was shorted, also will change out a couple of precision resistors in the regulator. Then I'll power it back up and sniff around, thanks for the boost supply idea I'll check that then.