In article ,
Woody wrote:
In practice if there is to be an earth within a hi-fi system there
should only ever be one and very often that used to be on the
turntable. If there is more than one you will likely end up with a
'hum loop' around the multiple earths causing a very low level but
continuous hum form the speakers.

I've never ever seen a system where the mains earth is provided via the
turntable. Most usually by the device where the mains is switched from
like the amp or pre-amp, if that supplies switched mains for other things.

Signal ground is a different matter.

--
*A conclusion is the place where you got tired of thinking *

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