Informative Soundproofing Discussion

Here's an excellent soundproofing discussion over at studio-central.com. The thread begins with the oft recommended carpet and foam wall technique, which, as you'll read, is a total no-no to some - although it's not quite unanimously opposed. The carpet opponents believe carpet and foam to be dangerous potential fire hazards that, lacking any significant mass, have minimal soundproofing ability - which is hotly debated due to many people adding their anecdotal evidence to the contrary.

The discussion offers many links to different, informative soundproofing resources, including this document called Exposing Acoustical Myths (PDF), which really breaks down a lot of the misconceptions people have about the science of soundproofing a space. Another nice resource is this page that details the different drywall, stud and insulation configurations and their corresponding STC ratings. STC ratings are, according to stcratings.com:

...a single-number rating of a material's or an assembly's ability to resist airborne sound transfer at the frequencies 125-4000 Hz. In general, a higher STC rating blocks more noise from transmitting through a partition.

So, the higher STC the better. Another site worth checking out is Acoustics.com. They've made available an Acoustics 101 overview page, as well as handy project design resources that give detailed tips on designing all sorts of different types of rooms, including home theatres.