Если кому интересно - статья от Overly Door Company: http://www.overly.com/door/tech/docs/monoAcs.pdf язык англицкий...
Там же - "Available Sound Control....": http://www.overly.com/door/tech/docs/wall-singleH-1-78.pdf
и http://www.overly.com/door/tech/docs/wall-wood-db.pdf - короче говоря "...must be grouted full in
field. Bolt-in type frames must have all voids in head and jambs packed with 6 to 12
pound density mineral wool and all voids between wall and frame continuously
caulked" и никакой пены...
Еще любопытное - "Breaker Bars": http://www.overly.com/door/tech/docs/bbar.pdf