Purchased a 4b and 1 P yesterday. Despite being ancient ( built in 1980) - both work . The only things I can find wrong are the inevitable E-core cover rattle (bag o shot will cure that) and the right channel measures 11 mV ( not anything to worry about) - the left measures 39mV DC and I would like to adjust this down into the less than 10mV range, ?
Q-1: where on the driver board is the dc offset pot ? What is it labeled as ( I love manufacturer's like Bryston who print device numbers on their boards - not something done by those that are going for a short run.)
Q-2: What is the spec for DC offset on these amps ? IOW -what should I adjust to ?
I briefly removed the cover on the 4B before purchase and noticed a VR on the driver board - but didn't see what it's labeled as and don't know if that's the only one on the board (wouldn't want to start screwing up bias when I thought I was adjusting DC offset!). Although the customer thought Bryston had only serviced a failed power switch some years ago - obviously they had also replaced the power supply caps - physically much smaller capacitors mounted on a board with a 94 or 96 date on it.
The surprise to me is the 1B Pre-amp. Had never heard one of these before and am very impressed with how good it's phono inputs are!
