Jeff: Drywall standard construction turns out to be excellent. If the room dimensions are right then you can do a 2 or 3 layer buildup. If not, you are actually going to want to lose some bass energy, so stick to single layer in that case. As to the "egg crate" foam. Most of that is very low density and not as good as the higher density Sonex, or even better is Owens Corning 703 fiber board wrapped in fabric.
You might want to get a book on Acoustics--Alton Everest Master Handbook of Acoustics is a good start. Our website and in particular, the listening room may prove to be helpful. The simulator there is also pretty fun when modelling a room.
You might want to get a book on Acoustics--Alton Everest Master Handbook of Acoustics is a good start. Our website and in particular, the listening room may prove to be helpful. The simulator there is also pretty fun when modelling a room.