Sound Proofing

Andreanm,

The cheapest and easier way might be to laminate your existing wall with Quietrock . http://www.quietrock.com/

i used foambymail.com 2 1/2 egg crate foam. it was wonderful.

Acoustic foam is not sound proofing. Foam (and all variations of treatment) is designed to diffuse or absorb or deflect sound. Acoustical TREATMENT does NOTHING to prevent audio transmission between rooms.

the ONLY way to prevent sound transmission between rooms is put mass between the rooms (concrete slab and lead panels work wonders). Quietrock can be part of the solution (there are others). Remember, sound travels via air -- and air gaps (even microscopic) help transmit sound -- that's why with any soundproofing solution, you will find some space-age adhesive or caulk as part of the design. You will also need to address the floor and ceiling -- simply buying $300 of acoustic foam can make your room sound good (less reflective, if that's desirable) but will do nothing to prevent transmission between rooms.

A solution for making an audio studio sound good will do nothing for you if your goal is reduction of transmission through walls

start here:
http://www.acoustics101.com/
http://www.acousticalsurfaces.com/

PS -- for windows, here is another resource:

http://www.cityproof.com/