Take a look at:
In general you want to block air exchange. Air caries sound very well.
(Try opening your car's window as a train is going by.)
Next you want weight. Heavy things (drywall lead sheets etc.) block
You also want to prevent any direct solid connections. Stagger wall
studs or use special isolation devices to keep the sound from traveling
through the wall (remember the two cans on a string (well wire actually
worked) you want to break the wire).
Filling in wall cavities with sound absorption materials (acoustical
fiberglass bats) will do a little.
Point source control (special absorb material) at the source of the
sound will also help.
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
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