Do properly shielded cases still exist? I need one!

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galneon

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Long ago, it was safe to assume the entirety of a case would be shielded (skeleton and shell). At some point, I stopped thinking about it, and only now did it dawn on me that my plastic and anodized aluminum case is only shielded on the back, bottom panel, and the mainboard tray. This does me no good as EMI leaks out the sides and front with impunity. This is a mess in a studio setup. The case is a CM HAF X which I'm otherwise happy with.

I need a similar full-size ATX case... Casters would be nice, but more importantly, it needs to be shielded. I will soon go from a modest home studio to a proper home studio so this is important to me for recording purposes. Manufacturers, in my experience, never talk about having fully grounded chassis plus side panels, front grilles, etc. Maybe they do for server cases, but that's not what I'm looking for.

I scraped off some of the anodized covering from the back of the case, added an alligator clip to it and now have a large sheet of aluminum foil attached to it by wire draped across the front. A terrible solution as it hampers intake, looks awful, and the cats love playing with it...

Shielding can be achieved with a Faraday cage--it need not be a sealed box, so small gaps are fine considering the wavelengths we're concerned about. This is why a fan grille is still compatible with becoming a part of a functional shield, assuming it's attached to ground which none of mine are.

Could anyone help me out by taking a multimeter to their cases and seeing how well-grounded the exterior elements are? You know you're curious! That would include checking things like front intake fan grilles, expansion bay grilles, removal side panels, etc. The easiest way to test is to unplug your PC from the wall and touch the ground plug of the AC cable to one probe of your multimeter and another to the part of the case you're testing for continuity. Make sure the PSU's switch is in ON mode for your tests. The meter should be set to the Ohm sign. Once you confirm one place has continuity with ground (like a screw attaching the PSU to the back of the case), you can go ahead and plug the PC back into the wall for the remainder of your tests assuming you are careful.

I'd really appreciate knowing if convenient options are available out there, or if I'm going to have a buy an all-metal case and then scrape, solder, clamp, and tape my own solution.
 
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I checked out every case on Newegg (wish I was exaggerating), and it seems my only hope is to buy a mostly-steel case with a front door and shield the back side of the door panel using copper tape, connecting it by wire to either the side panel or the frame near the hinge joint. This assumes the frame or the side panel, when in place, is grounded--who knows. If they aren't, additional work will be required, but I think with this case all of my modifications will be discreet. I'm going to try this out with a Define R5 and will post back on if I was able to sufficiently shield it or not.

This makes me wonder, how many people who responsibly strap themselves to ground when working inside their case are really clipping onto a grounded surface? Have your DMM handy just in case...
 
The only truly shielded cases that I know of are ones that are custom, I have seen some from the medical field but it has been a while and are big bucks usually.
 
Have you looked at the Silverstone Temjin series? They are entirely metal. I have a TJ11 which looks to be way too big for what you are trying to do, but they have a TJ06-E which is really small in comparison. While I havent verified all the panels are grounded via a meter, logic tells me everything should be. If its beneficial to you to know for certain if a TJ11 is, let me know and I will dig my meter out and test it.
 
galneon said:
Could anyone help me out by taking a multimeter to their cases and seeing how well-grounded the exterior elements are? You know you're curious!
Click to expand...

Hehe, you read my mind. We often have 'buzzing audio' threads and one time I got curious enough to do just that.
Some findings I made:
- front of the case -> PSU enclosure -> the "third pin" (yellow/green) in the PSU power cable socket -> 0 Ohms
- a case fan grill -> PSU enclosure -> "third pin" -> 0 Ohms
- motherboard tray screw -> PSU enclosure -> front of the case -> sides -> 0 Ohms
- "third pin" to PSU's secondary ground (black molex wires) -> 0 IIRC.

The only thing that was inconsistent was the time the multimeter finished the measuring - I had a feeling it sometimes takes like half a second longer.
I even checked the rear USB sockets. Cut off the second connector of a random A cable, and checked the grounds that are there. IIRC signal ground had 0 Ohms to chassis ground (socket enclosure).
This was over a month ago and I could be wrong.

I think you should invest in a proper EMF meter to get at this issue right.

One thing I found out in the course of my travels was that enclosing a soundcard within a folded piece of cardboard with aluminum foil glued to it DID allow me to listen to music louder without distortion. This was on two different soundcards and I know it wasn't placebo because I remembered where the volume dial was at before and after. Difference was tiny, but it was there.
 
The TJ06-E does look nice... I didn't check it out before because Newegg had only the mega-extended and micro versions. The TJ11 is $700, probably because availability is so low. I think I'll be able to fix the R5 Define up. I just have to scrape paint at hopefully hidden locations and line the door with copper, then it should be shielded from most angles. Waiting for more fans before I get on it.

I forgot to specify my goal isn't actually to keep EMI out, but to keep it in. :p I'm worried about my tube amp being noisy when recording, and my main source of noise comes from guitar pickups picking up noise from stuff around the house, and the PC is especially bad about this (fans, and I still have a couple HDDs in it which may or may not contribute much to the problem). Conventional guitar pickups are so crude. :(

michalrz, those are good results. What case was this? I wouldn't expect the meter to ever stay indefinitely on 0 ohms but anywhere near it is good for me. I recall having to isolate a soundcard from a GPU a long time ago for a similar problem. Now I mostly use an HDMI out for gaming/movies/music and, for more serious stuff, an external sound interface, so that's no longer an issue for me. Maybe I could make it an issue if I listen critically enough... but I think I have enough.
 
in that case wouldn't a good full steel case(no window) and emi shield fan filters or copper mesh be enough? istar has a bunch of 4u rack/desktop models that would work or any case with thicker gauge steel. if its the tube amp that's causing the problem maybe you could build a faraday cage for just it.
 
When I'm done with it the Define R5 should meet all of those requirements :) All components of the amp are in a shielded chassis minus the bottles of the tubes that stick out which don't seem to be a problem. Next time I take it apart, I will probably line the back side of the face plate (it's a head) with copper and attach it to the chassis, just for completeness. The problem with the tube amp isn't actually it picking up EMI directly (the baseline is more or less the same with the PC on or off), but it amplifying the EMI the pickups indiscriminately pick up.
 
I don't see why not as long as you connect it to ground, and it takes care of acoustic noise from within as well if you require that kind of silencing too. I have a lot of conductive adhesive copper foil on hand from shielding guitars I'll be using.
 
galneon said:
I forgot to specify my goal isn't actually to keep EMI out, but to keep it in. :p I'm worried about my tube amp being noisy when recording, and my main source of noise comes from guitar pickups picking up noise from stuff around the house, and the PC is especially bad about this (fans, and I still have a couple HDDs in it which may or may not contribute much to the problem). Conventional guitar pickups are so crude. :(

michalrz, those are good results. What case was this? I wouldn't expect the meter to ever stay indefinitely on 0 ohms but anywhere near it is good for me. I recall having to isolate a soundcard from a GPU a long time ago for a similar problem. Now I mostly use an HDMI out for gaming/movies/music and, for more serious stuff, an external sound interface, so that's no longer an issue for me. Maybe I could make it an issue if I listen critically enough... but I think I have enough.
Click to expand...

A switching power supply can cause... forgot the English word... thumping? in the powerlines? You might benefit from an online double conversion UPS, it should keep your power clean.
The case was totally vanilla. The most plain random one. Too bad we don't really see impedance, though. An ohmmeter might show 0, but it wouldn't be zero if the applied voltage would be AC.
It was binary, though. 0, or in the kiloohms range.
I tried to silence a buzzing soundcard once and basically went through every trick I could find online. Ultimately I had to give up - it must have been active PFC not playing nice with my board.
 
put it out of the room and run quality shielded cables or better yet run them in a grounded metal pipe into the room.
 
Most steel PC cases that are not painted on the inside should already be properly grounded for EMI. Though this may take some time to find as most retail PC cases are painted black on the inside now. However, if you look at complete PC systems from major OEM such as Dell, HP, etc... their cases are all unpainted on the inside so you could also look to salvage cases from these systems.

It's rare to hear a DIY user specifically looking for EMI shielded cases nowadays though, this is why currently we only sell a single retail tower case that has unpainted innards.
 
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H2R2P2 said:
Have you looked at the Silverstone Temjin series? They are entirely metal. I have a TJ11 which looks to be way too big for what you are trying to do, but they have a TJ06-E which is really small in comparison. While I havent verified all the panels are grounded via a meter, logic tells me everything should be. If its beneficial to you to know for certain if a TJ11 is, let me know and I will dig my meter out and test it.
Click to expand...
Temjins are sexy! Have a TJ09B, TJ09S, TJ08B and TJ08S.
 
Paint is the main problem, yes, but I have to wonder how much work it would be for manufacturers to leave a little bare metal around select screw holes or rivets in order to achieve the sort of grounding throughout which used to be standard.
 
galneon said:
Long ago, it was safe to assume the entirety of a case would be shielded (skeleton and shell). At some point, I stopped thinking about it, and only now did it dawn on me that my plastic and anodized aluminum case is only shielded on the back, bottom panel, and the mainboard tray. This does me no good as EMI leaks out the sides and front with impunity. This is a mess in a studio setup. The case is a CM HAF X which I'm otherwise happy with.

I need a similar full-size ATX case... Casters would be nice, but more importantly, it needs to be shielded. I will soon go from a modest home studio to a proper home studio so this is important to me for recording purposes. Manufacturers, in my experience, never talk about having fully grounded chassis plus side panels, front grilles, etc. Maybe they do for server cases, but that's not what I'm looking for.

I scraped off some of the anodized covering from the back of the case, added an alligator clip to it and now have a large sheet of aluminum foil attached to it by wire draped across the front. A terrible solution as it hampers intake, looks awful, and the cats love playing with it...

Shielding can be achieved with a Faraday cage--it need not be a sealed box, so small gaps are fine considering the wavelengths we're concerned about. This is why a fan grille is still compatible with becoming a part of a functional shield, assuming it's attached to ground which none of mine are.

Could anyone help me out by taking a multimeter to their cases and seeing how well-grounded the exterior elements are? You know you're curious! That would include checking things like front intake fan grilles, expansion bay grilles, removal side panels, etc. The easiest way to test is to unplug your PC from the wall and touch the ground plug of the AC cable to one probe of your multimeter and another to the part of the case you're testing for continuity. Make sure the PSU's switch is in ON mode for your tests. The meter should be set to the Ohm sign. Once you confirm one place has continuity with ground (like a screw attaching the PSU to the back of the case), you can go ahead and plug the PC back into the wall for the remainder of your tests assuming you are careful.

I'd really appreciate knowing if convenient options are available out there, or if I'm going to have a buy an all-metal case and then scrape, solder, clamp, and tape my own solution.
Click to expand...

Have you considered a rackmount case?

I have an Antec one here that's 100% steel and is unpainted on the inside. Rackmount is probably the configuration you'd be most likely to see for real studio-caliber audio equipment anyway.
 
Yeah, rackmount is pretty much what I was getting at with "server case' (though the NAS case mentioned the other day qualifies too). I still need the conventional form factor though. Just about done scraping paint here and there from the Define R5. Its side panels have no threading and thus had no connection to ground stock. I'll take some pics or at least say how it went when I'm done.
 
My caselabs seems like it'd be a good candidate, although they are fully powder coated ( you could probably get a custom conductive powder coat).... and cost a ton
 
This wasn't much work. On this particular case (Fractal Define R5) the bottom, back, top, and front were already grounded. That just left the door and the side panels to deal with. I filed back the paint and primer in some places and placed copper tape (with conductive adhesive side) over the raw metal. In the case of the door, I just taped the whole inside and ran a wire from it to the grounded interior front part of the frame. Continuity everywhere

Where the side panels meet with ground on each side of the rear of the case (the side panels have a corresponding filed and taped section):

case1.JPG

And the mostly shielded door:

case2.JPG

I've already tested, and it certainly helps with the guitars. Hardly lab-grade coverage, but good enough for me as I can change position and facing of the pickups when necessary.
 
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