I feel like I'm setting up a good "That's what she said" but what are some good examples of thick limp mass?
Josh
6' thick lead walls.
But that is often hard to achieve.
A good example of how to reduce sound transmission is this simple idea.
MASS-airspace-MASS.
So 2 walls that are NOT connected together, but have an airspace between them
Ideally each wall is double thick sheetrock on ONE side-NOT both sides (of each wall).
The sheetrock is on the outer sides of the walls. So if you are standing in the airspace (it does not need to be large enough to stand in-6 to 12" is usually fine) you would be looking at the studs and backside of the sheetrock.
Steel studs are better for stopping sound transmission. Wood studs are better for making the room sound better. So maybe steel on the outside and wood on the inside.
Also stagger the studs so they do not line up with each other. That way the flexible part of one wall is opposite the rigid part of the other.
Some LOOSE fiberglass is not a bad idea. You DO NOT want to pack it in.
Be sure to tape all joints (on each layer).
Each wall needs to stand on its own.
Use double doors (with 6 feet or so between them) and make sure they are HEAVY SOLID doors with firm tight seals.
Seal up all mechanical exits in the building. Gas line, electrical, AC entrances etc.
Seal up all wall outlets to prevent air leaks from getting through them.
Acoustical caulk is best-due to the flexibility over time.