Hi chesseroo,

Actually, you're partly correct--sort of. The acoustical maxim for isolating sound in a room is: the more dissimilar materials you present, the more absorption will take place. But you have to use offset studs so no vibration is conducted through the framing of the room. And you have to seal cracks and doors. Anyplace air can get through, sound waves will follow.

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)