Computer case with good EMI shielding

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Hi,
At the moment my recording studio computer emits so much EMI that I can not use single coil guitar pickups. The noise is awful. I've been looking at ways to improve/create a faraday cage but decided to buy a new case because there are a few on the market now that also have acoustic dampening for silent operation. That is a 'must have' for my recording studio.

So, do any of you know of a silent case that also has excellent EMI shielding? Ideally I would like to pay less than £100, also my CPU cooler (Cooler Master Hyper 212 EVO) stands about 159mm tall.

Thanks,
Andy
 
Zootalaws, I've tried scraping away paint to make good metal to metal contact but it seems to have made no difference. Also as I mentioned in my original post, acoustic dampening is important to me as it is in a recording studio, so I might as well buy a new case and kill two birds with one stone. And I don't want to go down the Mac route, not right now.
Thanks,
Andy
 
I had a computer like that and found in my case it was rf radiating back through the ac power lines. I found just using an isolation transformer solved my problem. Later I found that my computer power supply didn't have the rf filter components installed -- oh there was a place for the hash filter components on the pc board but the components had been left out .
 
Zootalaws, I've tried scraping away paint to make good metal to metal contact but it seems to have made no difference. Also as I mentioned in my original post, acoustic dampening is important to me as it is in a recording studio, so I might as well buy a new case and kill two birds with one stone. And I don't want to go down the Mac route, not right now.
Thanks,
Andy

I used to work on Tempest-rated computer gear - spook stuff, designed to be invisible to emf snoopers.

The inside of the cases was lined with copper foil, a bit like those fancy CD players.

The hard drives were shielded with a sandwich of copper and plastic, earthed. As were the big ASICS, plug-in cards, etc.

The biggest culprit is the vga card and cable. Very noisy.

You can buy adhesive copper foil on AliExpress.
 
Oh 20 years ago I ran across a pc hardened against RF . The cover was secured with 27 screws used to provide a uniform pressure to the metal mesh between the cover and case. And then there was the hash filter on the ac input. While most hash filters might use a pair of caps and a common mode choke or even 2 pairs of caps and a coppon mode choke this computer used a 3 pairs of caps and 2 common mode chokes in a C L C L C hash filter .
 
Thanks Woody, I hadn't considered noise on the power cord. The noise stops momentarily I I move the mouse or press a button on the keyboard. I've tried turning the computer on without them plugged in but the noise is still there, I suspect it is coming from the MOBO. Also my PSU isn't cheap, I'm not sure but I think it's a Corsair energy efficient 600W. I have a few ferrite rings somewhere and a filtered 6A IEC input, it's probably too big to fit inside the PSU if they haven't deliberately left space for one.

I had considered using copper foil, but knowing my luck it would eventually peel off and short something out, so I'd rather not try it. But if it comes to it, I may have no choice.

Recording electric guitars often involves so much signal gain that the guitar sound distorts. This also brings up the noise floor. Most guitarists are familiar with the problem. There is often a sweet-spot, with the guitar at the right angle, in the right place, the noise is at a minimum. My room is so small that even the sweet spot is too noisy.
 
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