I am setting up a home studio/theatre in my room, and wanted to reduce the noise my computer made. While there are other solutions like water cooling (a bit softer) and larger case fans (requiring a new case), I thought the best option would be to use a computer isolation case. Buying one would be a bit expensive, so I decided to make a cheap DIY case out of things I had lying around. You can get most of these items cheap and easily in local classifieds or the re-usables/recycling shop.
The isolation case aims to reduce the amount of sound emanating from the computer into the room, while still allowing airflow to cool the PC. Sound is attenuated by use of solid wooden panels, sound absorption material and corners/chambers so that there isn’t a direct path for the sound to exit the case. Inlet and outlet holes are strategically placed at the bottom and top rear of the case for efficient convection airflow while keeping noise away from the listening area. Note you should have enough space for air to flow out, especially at the rear. Another thing is to have enough space for cables, wifi dongles and provisions should be made for a frontal door if you wish to use the DVD drives. A way to turn on the PC without having to unscrew things would also be very helpful!
My case made use of a solid wooden cabinet (with doors and backing missing), carpet underlay excess (there’s always someone giving this stuff away) and random pieces of wood which you can get second hand or scavenge from another cabinet, etc. Or you can buy some from the hardware store. It just so happened that my cabinet allowed for a second chamber where the outlet fans blow air into.
Using templates of the computer case, I cut the ventilation holes with a jigsaw. You can make templates with paper the size of the top/bottom of the case and using a pencil to colour over the grills. This will give a nice easy area to cut out of the template. With my case I also added a direct top/bottom vent to create convection so as to rid the hot air from the rear of the PC.
I added caster wheels as this cabinet was heavy enough empty let alone with a PC and extra wooden panels attached to it!
The front panels screwed on.
The main rear panel for the isolation case. The strip sticking out was an attempt to reduce the amount of hot air flowing around into the GPU air vent.
Reducing Hard Drive Hum / Isolating HDD from the PC Case:
After test running the isolation case, I found the hard drive humming was still coming through the case due to its mechanical connection to the PC case and hence the isolation case. I also found out the need for extra space and a frontal door to access the DVD drives/power button! Despite these issues the case worked very well to reduce fan noise and the higher frequency noise from the hard drives.
I decided to DIY isolate the hard drives as well. Using a thin piece of aluminium, I made some brackets to hang the drives vertical in the 3.5″ bays. The drives would be hanging from a piece of rubber so that the low frequency hum wouldn’t transfer into the metal PC case.
The hooked edges are so I can use this rubber to loop around a small shelf above the 3.5″ bay. You could also use rubber strips to hang the drives, and then add some foam to stop them hitting the sides of the bay. Don’t compress the foam too much or else more hum will be transferred.
The drives inserted back into the PC. I should probably add a little foam to keep them in place more securely. So far there seems to be less hum, but the real test will be when I put the computer back into the isolation case.
That’s all for now, maybe you will gain some ideas from this post if you are also looking to build your own isolation case. Using newer materials and a bit of wood working can create a nicer looking case if you wish to put it on display. You can even use a glass front door 🙂