Check your interconnects and speaker wire first. One of my XLR ICs had a cracked solder joint resulting in volume drop. Try switching R to L and see what happens.
Harman Kardon A300
Hello everyone
I just did a full rebuild of this amp. Brought it up slowly with the variac and the B channel sounds great but the A channel is bad (really weak). I’ve fooled around with it now for a couple days and I’m starting to feel out of my skill set. Does anyone know of a good tech in the San Francisco Bay Area region? There used to be a couple places that were really good but audio technicians are a dying breed and hard to find. I’d be willing to deliver it anywhere in the state - don’t want to ship it since I’ve done a huge amount of aesthetic work on it and I’d hate for it to be damaged.