On soundproofing

Most people will find this post boring, but I assume it will come up when someone googles "how can i build a sound proof closet in my room."

My friend Adam is building a sound proof closet in his room, and I've been his assistant.  He is a musician and composer, and he wants a place where he can record his music.  So, his idea was to build a little booth in his bedroom and do his recording there.

I don't know if that sounds simple or not, but it isn't.  Building a small space for audio recording requires a lot of specialized techniques and materials if you want the quality of the recorded sound to be pure.  He couldn't record just in his bedroom because of all the ambient noise.  We don't notice these things every day, but the fan on a computer, the light hum of a lamp, noise from outside that carries through the window, and more all interfere with the quality of a recording.

There's no buildasoundproofclosetinmyroom.com, so Adam had to do a lot of research.  Turns out that there's a lot of disparate sites on the web with videos and instructions for soundproofing.  Adam got a sense of how big he wanted the booth to be (large enough to record someone playing a cello) and designed from there.  The wills are about 12 inches thick when you consider the insulation and coverings on the wall, so the booth takes up a lot of space in the room for just a little space inside the booth itself.

Soundproofing is a two-part process: elimination and absorption.  In constructing the booth, we used special caulk, thicker drywall, specific insulation and carpet to keep all the sound that exists outside the booth outside.

By making the booth so airtight so that vibrations can't get in or out, it also keeps air out.  To ensure no cellists suffocate, Adam also built a large ventilation system.  The box with two fans is about 4'x6'x1', with the fans and ventilation holes all askew so that sound doesn't travel through them.  It's also insulated itself with insulated ductwork.

The drywall is attached to the inside of the booth not to studs, but to "resilient channel," which is in turn attached to the studs behind the wall.  This means that any vibrations that come from the sound in the booth with hit the drywall, and then the vibrations are absorbed by metal channel and not transferred to the studs, which are connected to outside walls.  The walls and ceiling are build so soundproof that the weakest point in the booth is the "soundproof" door.

So, that's what I've learned about soundproofing.  I've also learned that when I type soundproofing, I usually type soundproffing and then have to go back and correct it.  That's happened many times in this muse.