My new PC is great but very noisy. Rather than get a quieter case which won’t even make it silent, Im thinking of building an mdf box to cover it. I would make several inches space between the box sides and PC with some foam cones inside each side.
Is this stupid in terms of overheating etc. I figure as long as there is sufficient space inbetweeb it should be ok? Anyone care to share their experience on this issue?
Al
Hey Al,
I’ve thought of the same idea but you’ve got to have air flow of some kind. Recirculating the same hot air will cause an overheat of the processor and other components. I was thinking of a box that would baffle the sound, allowing air to flow but absorbing the sounds of the fan(s). I would love to hear from someone who has come up with a design that works.
Chris
A possible solution would be to swap out the power supply and CPU coolers for quieter units. Thats where most of your noise comes from. I have an Antek Take4 rack-mount case with a Noctua 9 CPU cooler and an Enermax Pro87+ Power Supply and its as close to silent as I’ve ever heard. Noise is far below the noise floor of the room and undetectable during recording.
.
In 2006 I built a full iso box for a new rig.
5/8" particle board, 3/4" plywood base, sealed door with glass, carpet lined…it even had wheels.
It took a lot a work and even looked fairly snazzy…but it was a colossal failure.
Firstly, instead of suppressing the computer noise into blissful silence, it actually converted it to a strange low frequency rumble emitted out the (necessary) rear thermal openings.
It actually took the acoustic energy generated by the computer, and made it effectively louder by condensing it and altering it’s frequency like a megaphone.
Secondly, it made any maintenance and port/cable access to the machine an absolute feggin nightmare. 
I lived with it for about a month, trying various linings, portings etc, but just gave up and took it apart to use for shelving.
It was far more effective to get higher quality fans, high efficiency power supply and aftermarket CPU cooler, and hook all that up to the Zalman multi-fan speed controller I already had.
On my newer quad core build, components had advanced by miles to make them many times quieter than my previous machine. Hard drives, PSU’s and tower cases have come a long way. (Even the stock Intel CPU cooler was quiet enough to not require me to get an aftermarket one.)
On this machine, the BIOS also has fan settings for silent to high performance mode. Add to that my old Zalman fan controller and all I hear is a bit of fan noise.
Note: One component that has gone the other direction with regards to noise, is video cards. They come with small, high RPM fans that output only slightly less noise than a canister vacuum cleaner with dry bearings.
I replaced that nonsense with a Scythe heatpipe cooler and now my NVidia is essentially inaudible, and it doesn’t turn into a space heater when doing HD video transcoding or playback. (The heavy stock cooler was slapped on with a giant gob of thermal paste, and some of the peripheral chips weren’t even in contact with the cooler. Unbelievably shoddy assembly. Hardly a wonder the fan never spun down.)
You can get a proper iso box, but they are fairly big with usually sophisticated cooling systems, and cost a fortune. Fine for a big production studio.
But, for a project studio modern comps are fairly quiet and can be made near silent with quality aftermarket components like fanless PSU’s, SSD’s and coolers.
QuBe
if you want your PC more quiet?
your PC case is like a tin can, knock on it and you almost hear reverb 
fill a tin can with sand and it’s “dead”
so “weight” and “coupling” is the trick
I built my own as well 5 years ago. I took an Ikea kitchen furniture ( a little closet) with opening door on the front and the rear.
The hardest part was building a heat exhauster with sound absorbing foam and an air flow circuit that effectivily reduced the noise emitted by the lot. The key is to have some cool air intake at the front base and exhaust on rear top. The size of the box matters a lot too. The bigger, the cooler (if properly done).
It worked pretty well, was ugly 
and the overall comp temperature would only rise a few degrees compared to beeing outside the box.
The Antec Sonata and comparable comp cases + low noise fans are “sort of quiet” but usually not enough if absolute silence is what you wish.
I find the machine room to be the best solution once I got quality vga & hdmi, midi, ethernet long cables, usb repeaters etc. Costly but wow, ABSOLUTE silence !!!
± 5 years ago I had a similar problem=noisy computer.
I went for a server 19" rack case (±300 Euros without power supply).
The case itself was very heavy - but very high quality.
I have used acoustic foam - I glued (self adhesive) that into the case. I had a front case ventilator rotating at relatively slow speed, and I had Zalman quite power supply, and a Zalman cooler for the CPU.
The HDs were in silent enclosures…lots of work and budget, too.
Well, at the end the PC was very quite.
The bottom point is that all noise source ads up. So, you have to really chose the right components and surely the noise will go down.
But I think today’s components are rather “quite”… and you can certainly buy a “quite” PC.
Check:
This is all good advice from various experiences so thanks everyone.
Thinking my best option is to tolerate PC noise as I mostly use headphones. Instead, for vocal takes I have decided I will build a collapsable vocal shield (I’m not talking about SE electronics one…that is the single biggest disappointment to me in terms of gear bought). A vocal shield 7ft tall with a window. Seems like the only way ahead as i don’t want to start faffing about with the PC.
Cheers
Two other things you can try instead of dealing with computer bits…
Place sound absorption foam (not diffusion foam) on all surfaces near the computer
(if your comp is under a desk, place a foam covered board to make a little wall between it and you - it’s more effective than you’d think.)
Secondly, if circumstances permit, do a poor man’s machine room.
In other words, chuck your computer in the next room and drill a small cable hole through the wall.
I did this once…my PC was consigned a wall away in the corner of my bedroom, and I enjoyed a studio space free of fan rumble and hard drive whine. (in those days, hard drives were pure torture…I even toyed with building a little shed for it attached to my outside wall - the only thing that stopped me was lack of an external burner, and fear that rain would leak in and blow up my comp…or winter would seize my drives.) 
QuBe.
I’ve just only now seen your picture of the box you built. The box I was talking about would be several inches wider and taller all round. Would that make a difference for the better?
ok, let me try to explain, want to do something REALLY smart? take a chassis fan in your hand, extend the power lead someway and start moving it around in your case, around your case and furniture, notice the noise increases on REFLECTIONS, causing resonations? THAT’s what you want to attack. a fan out in the open barely makes noise, it’s the reflecting surface close by that makes the noise, to ONLY way to take that away is to absorb it. which turns vibration into thermals and dispenses it.
What are you saying I should do raphie? Sorry don’t follow?
first step, make your pc case “dead” (Dynamat or equivalent) take your case apart and apply that stuff everywhere you can get your fingers in
2nd step, proximity absorb with absorbtion panels (i.e. studiofoam, auralex etc)
you can do this in a “hushbox” type construction, but not to close to the fans, at least with a radius om 30cms on each side, or just by pasting some of these panels on nearby furniture (panel facing the PC)
you buy those panels normally in 12 pieces boxes, if you havent treated your room yet, i would just buy one of those boxes and spend 1 or 2 op these panels on surrounding your PC.
the essence of succes IS NOT closing up the PC, but it’s really about deflecting and aborbing the proximity of the PC
Ok agreed. I’ll give that a go. Thanks again.
Al
Hi Al,
Maybe I missed it, but can you tell us what is your case?
Photo?
By routing the cables inside can make a difference, too. I know that is not much, but any small step will help.
trif.
It might help.
The main design issue I found was ‘ventilation’ i.e. how the air (with all the noise) exit the box.
If there are just port cut outs rather than some sort baffling or diffusion system, the sound was just focused into a lower frequency rumble rather than dampened. This was compounded by the fact that the computer was located in a corner, so the focused sound just bounced off the walls.
But as has been mentioned, it’s much less work to swap out a few of the offending computer components and/or control the fan RPM, than it is to build any iso box.
A good quality case may be all that you need. I use an Antec Solo and it’s great - no iso box and there’s no hard drive sound whatsoever, and just a quite acceptable level of fan/exhaust noise.
QuBe.
Am going to just do vocals away from the PC. Seems like the simpler solution as I can tolerate the PC noise and it’s not too bad when I have headphones on.