cthomp said:
Which type of fiberglass insulation would be the better choice for sound insulation between floors in home theater application? My joists are 2x10
If you're hoping that fiberglass will absorb sound and prevent your HT from being audible in other rooms, you're probably in for disappointment. Insulation won't hurt, and it will help some, but bass will go straight through, faced or unfaced. Really stopping sound takes specialized (and expensive) techniques, and most people find it's not worth it.
If you want to just stop midrange and high frequency sound (most dialogue, some music), then pack in faced insulation with the facing side away from the sound source. Put up two layers of sheetrock, not one, on walls and ceiling, and you'll get fair amount of deadening.
If you want to go the whole hog, Google for "room within a room", homasote, and spring loaded ceilings. I went this route and while it is not cheap, it does stop everything but very loud, very deep bass, most of the time.