In article ,
Phil Allison wrote:

In the world of live music, I have come mixed class I / II systems that
are very scary.

In UK TV studios etc, before the days of RCDs etc, every single item of
unknown equipment - like say a guitar amp etc supplied by a musician - was
fed via a mains isolation transformer. Expensive and time consuming but
very necessary.

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*I'm planning to be spontaneous tomorrow *

Dave Plowman London SW
To e-mail, change noise into sound.