I just moved into a new home that has an existing bonus room that I will be using for my theater. 2 walls (1 outside wall and 1 tangent to garage) are insulated, but the 2 remaining interior walls are not. It's just me and my wife in the house now, so we'll likely be watching together most of the time and I don't have any concern about sound getting to the rest of the house.
I see lots of threads about decoupling the walls, double drywall and green glue etc... but does it matter in a situation like mine? Will sound resonate in the open channels between the sheetrock without insulation? And if so, can I use a "blow in" type insulation so I don't have to tear apart the walls?
The room is smaller than I would like to begin with (16.5'x 12.5'), so adding extra layers or a room within a room doesn't appeal to me. I'm not opposed to acoustical wall treatments though...