I'm planning my new home theater right now and like everyone here I'm having thoughts about soundproofing it, so I can bump the volume up without bothering anyone in the house and my neighbor who lives about 20 yd away.
Other than him I don't have anyone surrounding me, the HT room is at the far end of the house, no basement, but two rooms and a terrace above it.
Since the HT area will be added to the already existing house it has somewhat of a special connection to it.
The exterior wall of the house is a 10" thick hollow masonry wall. Then there is a 1 ft air gap and after that another 10" thick stone wall.
That's where the HT will connect to.
The HT itself has a 10 ft room next to it. So it is: "house -> 32" double wall with air gap -> room -> HT".
The exterior walls of the HT area are 10" thick and the interior walls are 5" thick hollow masonry walls.
Now I've read a lot in this forum and it seems most people build a decoupled stud wall with double drywall an it.
In my case I don't know if it is the right approach, since I already have the stone walls. And building it that way in addition would take a lot of space out of my room.
So my question is what is the best way to go and how much sound reduction would I get?
I thought about building just the wooden frame, fill it with insulation and add one or two layer of drywall.
The other idea was to build it staggered or going all the way of a double stud wall.
The whole decoupling thing makes sense if I would have just the drywall, but having the masonry wall I don't know if it is worth it.
I'm aiming for a good amount of reduction. It doesn't have to be totally quiet, but not as loud so everyone outside the room will hear what movie is playing.
Listening volume will be around reference level.
My primary concern is the overall volume outside the room. Low and subsonic frequencies aren't important right now.
I doubt they travel the distance through the entire building. And since I don't have anything and anyone else around my HT I'm not concerned about the LF/ULF. Or should I be?