Some people seemed to have hum issues but I didn’t particularly. It’s just the phono stage that really needs the quietest valves. The line stage isn’t quite so critical.
I did try the Douk recommended power transformer but I had one that failed after a couple of months & then another that went the same way. Odd really because this circuit isn’t really stressing it. I was pondering getting one of these for the next one augmented by a small 12V transformer for the filaments.
It’s also worth incorporating a small choke in the psu if you’ve room. @coco re-simmed the RIAA network arriving at slightly different values to get it more accurate Did you get the switch on an umbilical to engage/disengage the relays?
I have a couple of more boards to build up so may try a very foo-ey one next time.
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