Hi guys,
I've noticed in a lot of HT rooms the side speakers are often housed in full-height buttresses -- "steps" in the side walls that protrude into the room.
Is there an accoustical reason for these? Or is it just that the surround speakers can't fit into the wall cavities? I'm thinking they could be there as bass traps, or they may do something to break up standing waves.
I incorporated them into my own room diagrams, assuming they serve a purpose:
http://www.wychwood.net.au/floorplans.html