I built an ST70 from scratch, point to point wiring for my first project. I used new Dynaco repro transformers from Triode, upgraded cap psb from Triode, JJ Tubes, and the driver board is the DIYTube design.
Here are my problems:
1.) I had to disconnect the 16 ohm leads to the negative feedback because of horrible buzzing. It is now fairly quiet, but I would rather have those leads connected.
2.) It plays music without any buzzing, however there is a quality to the music I guess I would describe as distortion.
3.) I am also a little unclear on where I am supposed to be measuring the 400 then 500 mv when biasing. What terminals exactly should I be putting my multimeter?
Any suggestions on where to look?
thanks.