290ma? That is a lot so the raw AC is probably much higher than that but it depends on the regulation of the transformer. You should be getting around 500VDC raw off the rectifiers with that setup.
All Lambdas have the earpads glued to the baffle, including all of the new ones. Only difference is that with the new ones the drivers aren't glued to the other side of the plate but mounted in housings instead.
The Lambda Signature was released in 1987 so six years prior to the SR-Omega. All the SR-1 through 5 units had loose earpads only fixed in place with small adhesive dots.
I have some of those but haven't tested them yet. They will go in a BHSE so that will see if they actually work. The lead wires the use are the worst I've ever come across. Nasty, cheap stuff.
There is no spec available for these transformers, not even in the service manual. I did replace one in a 100V (SRA-10S) unit and used these specs, 520VCT-100ma, 52VCT-250mA
They are not all the same but most are of similar quality. Those that I just got are from China but feel a lot nicer. Need to do some more testing though...
There can be other factors as this is sour dough. Too much activity in the starter leads to unstable dough and too much flavor. Sour dough is not supposed to taste sour at all...
Yeah, that stuff should never be used.
As for the 15-18V, are you talking about offset or balance? The amp drifts a lot as it warms up but you might need to adjust the series resistor in the offset adjustment.
The reason we use green boards is to easily spot any shorts so if you can't see any then the board isn't at fault.
There isn't enough power in this circuit to cause anything like this so it has to be a short, bad part or something like that.
It's likely rising too much so not enough salt. The golden rule is 30gr per 1L of water. You can go up to 40gr for more flavor but also slower rise time.