60,

You must get in trouble with the wife all the time misinterpreting what people say.  Mattress on the ceiling?  :'(

Bob,

I was just making sure those recessed boxes weren't highly reflective.  Is it a basement?  If so, which walls are concrete?  Sure room treatments can always help, but from the photos it doesn't look like something I'd be in a rush to blame.  Unless you have some parallel concrete walls creating havok with room modes, you can throw room treatments under the header "fine tuning" on your list.  A 20-200hz tone sweep, can tell you if you have mode problems.  That will also reveal any holes in response with your sub/mains integration.  

I was asking what's behind that wall in front, not behind the screen.  Can't put a sub behind a screen anyway...too much air movement.

Technically, mattresses on the ceiling would work for higher frequency bass, at least to some extent.  Placing them standing up, across a corner, however, would probably get a lot more mileage out of them, and work on a broader range of frequencies.

John, it is a basement. 3 walls are concrete. Front, (behind the screen), the Back, and right walls are your standard basement foundation walls. Standard 2X4 walls with insulation. The only wall that deviates from the norm is the back wall. The drywall is somewhere around 8" or 9" from the concrete. This was done so I could avoid the various ugly "drywall framed boxes" people use to 'encase' the plumbing. I wanted a cleaner look. All walls in the basement are insulated with 'the usual', including interior walls.

Ok, who's comin' over to help with the mattress installation?  :-/ I'm going for all walls, floor and ceiling.  :-*

Ok, not really.

Bob

Line your walls with old mattresses from the "junk store", saves money on drywall. Saves time on mudding the joints.  ;D
And just think, NO PAINTING!

Bob

[quote author=Bob in St. Louis  link=1145573673/225#234 date=1149855507]Line your walls with old mattresses from the "junk store", saves money on drywall. Saves time on mudding the joints.  ;D
And just think, NO PAINTING!
Bob [/quote]

Ya, you don't have to paint because someone already beat you to the punch  :)
That's why it's in a junk store

[quote author=John in CR  link=1145573673/225#231 date=1149817518]60,

Are you sure you aren't from Mississippi?

Those of us from Louisiana thank God on a daily basis for giving us Mississippi.  That way someone else gets to be #50 in almost every category. [/quote]

i must be number 51, i have no idea what you just said.

[quote author=John in CR  link=1145573673/225#237 date=1149868616]How much air volume do you think is enclosed with that back wall?

How difficult would it be to move that front cabinet/shelf unit away from the front wall? [/quote]

Are you looking for the volume behind drywall including the 4" insulation, or volume between back of insulation to the concrete?

Horrible PITA to move cabinets. Don't know if it's possible with the way the screen attaches to the wall. (wouldn't have a wall to fasten to anymore if it's moved out)

Bob