I can relate being new to the process. Google searches bring up all kinds of products with impressive promises. Then you come to a place like this that debunks those myths and dares to look at the science behind it all.
Spend a good deal of time here studying all you can. Start
HERE at the "Before You Post" announcement. You'll learn that the most efficient means of "soundproofing" (I use the term loosely because there truly is no such thing) is a principle known as "mass-air-mass" (or sometimes referred to as "mass-spring-mass"), abbreviated as MAM or M-A-M (or MSM or M-S-M) -- a two leaf system. Each "mass" is considered a "leaf." The more mass, the better. The wider the air gap, the better. Insulation counts as air
if you can breathe through it. Generally speaking, you get the most bang for your buck using multiple layers of ordinary drywall. Sure, there are speciality products out there -- some of which have been proven to work, others that haven't -- but they tend to be very expensive relative to what you can do with more conventional building products.
Learn what STC is, and then realize that for your purposes, it is probably
not a valid measure, given its limited spectrum.
This post is intended to pique your interest and prompt you to do more research here -- not necessarily a point-by-point Q&A. Once you've done a good amount of research, you may become disappointed at how
hard it is to achieve good isolation, and you'll
wish there were inexpensive magical products out there that work as a substitute.
At this point, I'd say you're at Stage 7 on my (in)famous
Stages of Soundproofing Enlightenment.
I'm here to tell you that it
is difficult, but
not impossible, and you'll find a lot of support here for your specific how-to questions
after you've done your homework.
--Keith
