In article ,
tony sayer wrote:
Yes and no .. you some times need something light weight and absorbent
to improve the room acoustics which can improve the sound isolation such
as Rockwool or Earthwool..

That's modifying the acoustic. A barrier to prevent sound transmission
generally needs mass. Of course if you're using a double skinned one, some
form of treatment between the two may reduce resonances.

--
*Cleaned by Stevie Wonder, checked by David Blunkett*

Dave Plowman London SW
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