Wrapping power cords and interconnects with copper foil.

https://forum.psaudio.com/t/shielding-for-power-cords/37521/4

I can't speak for cables or interconnects but I had a noise issue with a tube preamp that regular Tin foil cured. 

I had hooked up an older tube preamp in my living room about a year ago. Right next to the TV..a couple feet away from a modem & router as well. The pre was putting a lot of noise in the chain. I switched out the tubes thinking they might have gone extremely microphonic sitting in the garage unused for over a year. 

New tubes made no difference. As I was jiggling & checking the rca inputs/outputs I noticed a change in the noise. Went into the kitchen and ripped off a square of Reynolds Wrap tin foil. Laid it over the back of the preamp & all the noise went away. Like wow. Obviously it looked pretty silly so I moved the preamp into the spare bedroom system which has no digital or wifi products. No issues in that room with that preamp & noise. In the living room  that little piece of thick aluminum foil was definitely blocking some intrusive noise wavelengths. 

Reminds me of the movie "Signs".

@carlsbad2 

There's some humor involved  in all of this. In the audio world, nothing new there, but I was unaware of the theory that shielding interconnects was disadvantageous due to inductive effects.  How does that work?  You wouldn't expect interconnects to radiate much energy, true, but shielding power cords makes a lot of sense. But wouldn't your interconnects need protection from the power cords?  Or would they already be ok if you were using good power cords?  Even worse, could you get I’m away & unavailable :) with el cheapo power cords by simply foil-wrapping them?  People are spending thousands of dollars for those things, maybe not needed if you can wrap a stock thick Belden cable with foil?  Maybe @tubelvr1 should have left his wrap job on just the power cables and it was overkill to do the interconnects. 

Sorry. The Apple "I'm away and unavailable" monster got in there.