In article , Dave Plowman (News) wrote:
Turn your amplifier on, with no music playing and listen. Leave the
volume control in the normal listening position and sit in your
listening chair. What can you hear? Anything? Of course not. And what
little hiss there is comes from the front end of the amplifier. None
of it comes from the mains.

You've never heard things like a fridge splat etc which is mains borne? Of
course it depends on the design of the power supply in your amp, etc.

I've got a dedicated radial circuit with its own earth feeding my AV
equipment.

I've got all my electrical equipment plugged into the normal wiring that came
with the house, no fancy filters anywhere, nothing special at all, and have
never heard any splats from my loudspeakers since I stopped listening to AM
radio. There's no audible hiss from a normal listening position either, even
if I turn the volume control to its upper endstop. (Normal listening requires
about a quarter turn). My audio and video equipment is not the sort of silly
pretentious stuff that costs a king's ransom, and it's not cheap rubbish
either, just carefully chosen well-designed gear that works.

Rod.