On Wed, 29 Nov 2017 18:20:16 +0000, Dave Plowman (News) wrote:

In article ,
Johnny B Good wrote:

One final note, it's good practice to power all of the components of a
"separates" Hi-Fi setup from a single ring main socket[1] via a quality
mains multi-socket extension lead or specialist connection strip. This
neatly isolates ground loop currents that can occur when using
different sockets on a ring main due to induced currents from heavy
loads such as washing machines, toasters, kettles etc.

I have a dedicated AV radial circuit here. With the earth for that going
light back to the house earth. Not sure that bit makes any difference,
though, but no big deal when installing it.

It shouldn't. Assuming you only have a single safety earth connection to
the common signal ground return, the whole thing could be left to float
at whatever induced mains voltage happens to occur (including half mains
from filters or even a full contact to the live). It won't make any
difference although I'd be rather leery of actually touching any of the
kit if bringing your hand to within close proximity generates even the
slightest hint of mains hum.

--
Johnny B Good