Originally Posted by EJ Husker1
On the backside of the 250 cubic foot space, I am planning a soundproof wall (decoupled framing/double drywall/green glue). Will that not limit the sound out from a IB setup or is a IB nearly impossible to contain?
I don't quite understand your comment on a SBA pressure wave. Do you mean that reflections from the back of the space will radiate back forward through the screen wall to the seating area? I had thought of lining the back wall with linacoustic or something similar help deaden the wall inside the 250 cubic feet area. Maybe I shouldn't do that?
The backchamber of a IB is basically the inside of a huge sealed sub, not impossible but needs good planning and execution to minimize LFE transference.
Your on the right track.
My utility room is my backchamber, it's lined with 9" pink fluffy all the walls, and I did my best at sealing so the wave would not leak out.
Honestly at "normal" HT listening levels , -15db MV, it totally works can't really hear it on main floor.
However when you run say -3db or 0db MV it does transfer upstairs thru the home.
No matter what, containing LFE is not practical unless your room is a sealed concrete bunker, only a few I know have done that.
Read this on SBA
If I had a re-do on my home, I'd have put the HT under the garage, and fully encased the 4 walls with engineered foundation walls with a 30" IB chamber up-front and use (4) 24" SI drivers and then 36" deep rear for absorption depth.
engineered foundation walls have studs 24" on center which helps absorb above 20hz energy.
For my HT, I used 2x6 and offset stud construction, so all 4 my walls have drywall on 24" centers.
Going the IB route, if you choose a line-array on the bottom that helps by anchoring it to the floor and also having braces from your wall front to the back wall.
Or, using a IB manifold will allow cancellations of speaker cone movement.
Consider how you will get into your IB backchamber to install/service.