SH...you keep saying soffit. I am thinking along the lines of a 3 sided indention, like a small closet with no door, to house my SVS cylinder sub. When I think of a soffit I think of something built out into the room, like a soffit at a ceiling to hide duct work, plumbing pipes, etc. The nook would be out of the room, and would be built with walls angling towards the room...like a big horn loaded sub. I would build it out of masonry (part of the basement foundation), and then use speaker cloth to create a seamless wall across the opening. My wife would be happy to have the sub out of sight and I could kill 2 birds with one stone.

I guess I was just hoping there would have been a sonic benefit to doing this, and perhaps a room coupling that would give me at least as much gain as corner placement does. Thanks for the reply, I guess this idea is junk.