I was taking a look at a Concert Bass (Silver & Black from 1973) and noticed a trim pot inside, I did find any info on it in a search of the board (and the schematic scan is a bit too blurry for my eyes) so, what exactly is the trim pot for?
The Trim pot is for biasing the output transistors...
My advice...
don't mess with it unless you know what you are doing and have the correct test equipment set up..
The signature tone comes from the transformer driving the output transistors...
You will notice a squiggly thingie at the base of each output...that is the drive transformer.
one proimary and four secondaries.
The bias adjustment is for the primary.
