Nasty high pitches tone

[Dr Bunsen Honeydew]

There are a number of fixes that *may* work, but nothing guaranteed as it depend on source. Ferrite rings, BMU, Mains Regenerator, building a Faraday Cage around the hi-fi https://www.youtube.com/watch?v=DQe3B_59kgw

[Ed345]

I think my skull is too thick to worry about the physical effects. More worried about my mental health from the bloody tone.

[Daniel Quinn]

stick the amp in card board box - put holes in for mains lead and speaker cable . wrap the cardboard box in tin foil . Hey presto a faraday cage .

edit - I should have said aluminium foil , I forget that tin foil is a northern colloquialism .

[Dr Bunsen Honeydew]

I think you missed the point. That video was about health but is just as applicable to your hi-fi. Daft as it seems if you build a Faraday Cage around your hi-fi (probably impracticable) it will almost certainly solve the problem. As in https://www.youtube.com/watch?v=EoQZY1FtI3c

I have known in the past someone to line the walls and floor (carpet on top) of their listening room with allumium foil. And don't listen to anyone talking about adding an earth to the cage, it ruins it as the earth becomes a source of noise. A Faraday Cage should float (electrically).

[Shevans]

And don't listen to anyone talking about adding an earth to the cage, it ruins it as the earth becomes a source of noise. A Faraday Cage should float (electrically).

Absolutely, and if its RF causing the noise adding an earth just makes the receiving aerial (input on amp) more efficient which give you more noise

[wallace]

Whatever you do,don't ask Russ Andrews,or he will sell you something for ten grand that all his customers swear by,,or swear at...

[Ed345]

I tried wrapping a few layers of tin (aluminium) foil around the amp, but it made no difference to the high pitched tone and increased the slight background noise.

[Fretless]

Does the tone also disappear if there are no input interconnects attached to the amp? If so then those cables could be acting as aerials.

[Ed345]

No, the tone is consistent regardless of interconnects connected, or source selected.

[terrybooth]

I tried wrapping a few layers of tin (aluminium) foil around the amp, but it made no difference to the high pitched tone and increased the slight background noise.

Which amp? Metal bodied one. I think the foil needs some space to act as a Faraday cage - hence the idea of forming it around a cardboard box larger than the amp.