EMI absorbers for transformer noise

What would be some recommended materials for lining my amp’s inner walls with, especially around the transformers (2x 650VA)?
I’m getting phono stage hum from the amp at around 2ft away. I’m guessing the turntable grounding wire is picking up most of this as its placement greatly affect the hum intensity, so would also like tips on what to use as a proper ground wire.

Do you get the hum if you move the phono stage more than 2ft. from the amp or are you hearing transformer hum?

If the former, its vastly easier to put some distance between them vs. trying to shield the transformers.

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Well, I can’t currently afford longer high-quality interconnects.
I’d like to shield the transformers anyway, I don’t want them leaking to any part of my system, however negligibly.
What would be a cost-effective EM absorbant for mains freqs?

Hi Arenith,

You could try the EMI sheets from Oyaide (some more details are on http://www.osageaudio.com/Oyaide.html).
You could try to put the sheets on top and at the bottum of the amp. But I doubt if it will work.

You could also try shileding your phono cable / RCA cable with shielding tape (https://hollandshielding.com/EMI-shielding-tape).

Of course, you can also try XLR cables/connectors but this is more costly compared to the 2 ideas above.

Are you could call the real pros @PSA

Very interested in your findings!

You could try this stuff. It costs pennies because it’s not audiophile. I used art on my switch, when I had one.


Over here they sell it on Amazon for £30 ($40) for 1.8 sqm.

1.8sqm of the Oyaide stuff would cost $3,490.62, but you’d probably get a discount.

I had the same issue because I actually stacked my phono stage on my turntable power supply. A bit stupid. I moved them apart and hum is gone. The expensive cables issue was solved by using cheap cables that I found in the attic.