Reply To: SC2.2 voltage regulator

[Ted Fletcher]

The design of that output stage is complex…. it is not symmetrical as it performs the matrix function of re-combining M+S/M-S into the L and R.

If, as you say, the noise remains the same when the output gain control is turned down, the the problem is associated with the output stage.

The difference in noise behaviour has to be to do with the way the ground paths are arranged. If I had the unit here and wanted to achieve the very lowest noise levels, I would experiment with some very heavy copper wire to try to eliminate the track paths that carry grounds from more than one place.