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Easy free tweak -- dealing with RFI/EMI -- try it and see?

With some Ciamara credit available I thought I'd try the Stillpoints ERS paper on the insides of my fuse box and Torus wall transformer to see if it helped improve things in my system. Treating fuse cabinets is a fairly well known application of this product which is designed to absorb stray RF and other electronic nasties

Well here I was tweaking away and I thought, golly the system sounds really clean and open and I haven't put the paper in yet -- I assume it will be even better with it!

Imagine my surprise to discover I'd been listening to the system with the fuse box/panelboard cover open! Turns out one of the best things to do with EMI and RFI may not be to enclose it in a metal box in the first place 🤓

And actually with it closed, with or without the ERS paper it sounded much more closed in, with a loss of low level detail

Same went for the door on my Torus transformer -- from now on I'll leave it open for serious listening -- there is a bit more audible transformer hum but as it's in another room this is no big deal

Anyway this is a dead easy free tweak so give it a try -- you may like the results
folkfreak
nonoise's avatar
nonoise
4,382 posts
 
Ghosts in the machine now, eh?
😈👻👺
jea48
2,944 posts
 
If you are indeed hearing a difference with the electrical panel cover open I don’t think it is because of EMI/RFI.

geoffkait may be on the right track with his theory about the magnetic field, don’t know for sure. There is a magnetic field that extends out around the current carrying conductor internal parts of the breakers. That would include out the breaker handle front of the breaker. Every other breaker down each side of the panel is on the opposite leg. (L1, L2, L1, L2, L1, L2, and so on). I would think the magnetic fields, of breakers with connected loads, would somewhat cancel each other out. Don’t know for sure. Introduce a ferrous steel cover in close proximity of the front of the breakers may have some effect on the magnetic fields of the breakers. Again, don’t know for sure.


You really need to run ABX listening tests to prove what you are hearing is real, and not just imagined. I suggest you have someone open and close the door for the ABX test and then you listen for differences. If you can correctly identify X  90% of the time then you are indeed hearing something. The why?

You should run at least 10 or 12 trials.
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geoffkait's avatar
geoffkait
14,147 posts
 
For the same reason all transformers, especially those big honking output transformers, should be wrapped with low frequency high permeability mu metal. For very best results wrap the transformer twice leaving a 1/4" space between the sheets. As for the ERS stuff I’d be very careful with it while experimenting. Listen for the sound becoming wooly or weird sounding. Wooly, bully. I recall distinctly hearing the ERS paper hurt the sound when a sheet of it was sitting on a coffee table in the listening room. I also heard it hurt the sound when it was moved to another room. I'm not hot doggin' ya.
don_c55
823 posts
 
EMI and RFI is almost all, "through the air" interference, and not significant in power lines.

Unless you live near a hospital, industrial park, or have motors turning off and on, on your power line. Motors that "freewheel" will generate noise back into the power line.

Opening and closing the door on the breaker box and hearing a difference is in your imagination!
theaudiotweak
1,793 posts
 
I removed the cover from my breaker box some 10 years ago as the this reduces the surface area of shear to populate and then travel on the solid core path to the high fi. transformers. Tom
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