The Best Soundproofing Materials
So, you want to soundproof your closet, or maybe even your whole bedroom, so you can play your music as loudly as you want to, without your parents popping in and telling you to turn it down -- or even off. Having a soundproofing consultant come in and evaluate your space for you is probably going to run a little high, compared to your allowance, but the good news is that you have many items lying around your house that would work quite well for a sound absorption check.
Choose several different materials, such as carpet, cardboard, plywood, foam, and bath towels, to test for sound absorption. Line your closet door with each material after you've placed a noise source inside and shut the door. To ensure uniformity, you probably want to have a prerecorded sound sample that you'll play for each soundproofing material. After you've lined the door, set the noise source to play, and then close the door. Record the noise you hear outside with an MP3 device.
After you've tested all of your materials, download each sound file to your media software. Then, read the results on the audio meters on your software package to find out which material absorbed the most sound -- and kept it from coming out in the hall. You'll probably find that your more porous materials work more effectively than smooth ones; the sound just burrows its way into the holes. Smooth, hard surfaces can deflect noise away from the subject, instead of helping to build energy.