In a previous post, we covered ways of soundproofing your studio to protect it from external noises. But what about noise being generated inside your recording space?
After I had successfully set up my own home recording studio and began practicing with my equipment, I was surprised to find that there was a persistent hum in the background of all my vocal tracks.
Unwanted background sound has no place in voicework. Not only is it distracting to the listener, but it is also highly unprofessional and may even cost you a job.
I did everything I could to isolate the source of this unwanted noise. Imagine my surprise when I discovered that it was coming from the fan inside the computer I was using to record my audio tracks!
In order to avoid this problem you have four options: the first is to upgrade the fan in your computer. There are several quiet options on the market, but you may lack the expertise to perform such an installation. The second is to purchase a brand new computer with a quiet fan. This is the most expensive option, and should only be used as a last resort. If your home recording studio is inside your house or apartment, you can simply drill a hole in the wall and place the computer tower outside of the recording environment. but because I opted for a stand-alone structure, this was not an option for me. The 4th auction, and the one which I chose was to build what my friends affectionately refer to as a “whisper box.”
A whisper box is basically a tiny soundproof room for your computer. This post will focus on how to make one. I’ll include links to all the materials we discuss at the end.
The first thing you’ll need to do is choose the box. I opted for the greenmade storage tote (see fig 1). In addition to being 100% recyclable, at $12 each it certainly won’t break the bank. And at 30 inches long by 20 inches wide and 14inches of deep, it should provide ample room for most home computers. You will, of course, want to measure your computer before purchasing a box.
After you’ve got your box, the first step will be to cut a square hole in one of the shorter side walls. (See figure 2). I recommend making it square, because it will be easier to cut than a round hole, and also easier to cover with duct tape. The tape will protect your fingers and your cords from any rough edges.
Next you’ll need to choose a method of insulation for the box. I recommend Owens Corning’s “Foamular” rigid foam insulation. A 2 inch thick board sells for about $30. The boards are 48 in wide and 8 ft long, which should be more than enough to cover the inside of your box.
Foamular is very easy to cut using a standard utility knife. Just draw a line with a ruler and pencil, cut, and snap. But make sure before cutting the board that you measure the length of each side at both the bottom and the top! These boxes tend to be slightly smaller at the bottom than they are at the top in order to allow you to stack them inside of each other when not in use.
once you have the dimensions necessary for each of the long side walls and short side walls, cut the pieces and slide them into the box. (See figure 3) Protip: measure twice before you cut & always make the pieces a little larger instead of smaller. You can always trim some off, but it’s impossible to put some back on.
Once all four pieces fit securely inside the box, use your utility knife to cut a matching hole for your cords in the foam board (see figure 4). I did this by leaving the board in place and simply cutting through the pre-existing hole in the box.
Add more duct tape to secure the board to the sidewall, and add an additional strip of tape all the way around the bottom of the board securing it to the base of the box as well. This will protect it from leakage during the next step (see figure 5).
You will have noticed in figure 4 that there are some remaining gaps between the outer wall of the box, and the inner wall of the foam board. In order to truly soundproof the box we are going to fill the gaps with spray foam insulation. I used Loctite Tite Foam. Make sure you buy the can for small gaps and cracks.
Protip: spray foam expands dramatically. So when applying it, less is more.
Another reason why I chose the greenmade storage tote, is that it’s unique lid has a rectangular depression which just so happens to be the same sickness as the Owens Corning foamular board.
We don’t just once to insulate for walls and let the sound leak out through the roof, so cut your last piece of foam board, inserted into the depression in the lid, and secure it with duct tape. (See figure 7). You won’t need to insuklate the bottom of the box, because the ground will absorb any vibrations strong enough to make their way through the plastic.
Congratulations! You are ready to use your whisper box. Put it in place, and run all of the relevant cables through the hole. I recommend plugging the hole with a small hand towel. (see figure 8)
Remember: computers have fans because they are designed to work at cooler temperatures. A computer that overheats will shut itself down. So do not leave your computer running in the whisper box with the lid on unless you are recording. (see figure 9)
Greenmade Storage Tote:
Owens Corning Foamular Board:
Loctite Tite Foam