I am having insulation (Optima) blown into my exterior walls and wondering whether to insulate an interior wall as well.

Supposedly the material is not sound dampening but acts as a reasonably good sound barrier. Definately cuts down the air motion. I have a big room (38'x 19') with a hallway entrance along one of the long walls. The hallway has a bedroom and a bathroom along it's side and 3 more at it's end.

The question I have is whether it is useful to insulate the wall between the hallway with bedrooms and the big room. The bed rooms at the end of the hallway are more important (kids and our room) than the rooms adjacent to the great room (guest room and baths). I am trying to figure out whether better insulation that won't absorb sound will help SPLs for the sub but shoot high and low frequency sounds down the hallway or will it restrict the overall sound transmission.