Rereading your mail, I guess I misunderstood your request.
One tip and one ring allows unbalanced mono connections only, while one
tip and two rings allow balanced mono or unbalanced stereo connections.
Anyway, using a ground-lift to solve a noise issue is dangerous. We all
experienced this issue. I add a switch to one of my 19" effects, but we
shouldn't do this. If you're using a ground-lift, at least take care
that it's not simply completely disconnecting from ground, it's better
when there still is a connection to ground by a capacitor.
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