Here's one suggestion. I believe it's worth your while to go to www.rpginc.com and download the demo of Room Optimizer. Play with it a little and then arrange to buy a copy of their Room Optimizer program so you can actually start modeling your room's acoustic response for various speaker and listener positions. It is $99 and can only be ordered via phone or fax. They then e-mail out the program in a few days (can you believe the delay?).
Once you have the full version you can set up the parameters to exactly match your room, seating, and speakers. Then let it run for a while and show you how good or bad various arrangements are likely to work. It's not an exact result, but it's pretty good at showing the worst peaks and troughs in your room response. Remember that it might be possible to have the speakers under or behind some screen arrangements. Also as you pull the speakers further into the room you gain some ability to bring them farther from the side walls. Extreme corner placement is unlikely to give a good in room response, but we can postulate until we're blue in the face. At least Room Optimizer will give you some idea of what to expect at differing positions and even offer some suggestions for best placement. If you are going to the expense of putting in a room, the money spent for the chance to do some acoustic modeling is probably worth it.
There are some classic rules of thum speaker placement methods at
http://www.cardas.com/insights/roomsetup.html
http://www.audioasylum.com/audio/faq/audiophysic.html
http://www.tnt-audio.com/casse/waspe.html
http://www.immediasound.com/Speakersetup.html
to peruse. I don't necessarily espouse any one of them, but they do provide some good reading. I don't think any of them conform to the limitations you are presetting. I list them here just to give you some other approaches.
In my mind, the sound system should be designed to do well for stereo sound reproduction as well as movie sound tracks. Why limit oneself to mere theater sound when you can aim for both?
Once you have the full version you can set up the parameters to exactly match your room, seating, and speakers. Then let it run for a while and show you how good or bad various arrangements are likely to work. It's not an exact result, but it's pretty good at showing the worst peaks and troughs in your room response. Remember that it might be possible to have the speakers under or behind some screen arrangements. Also as you pull the speakers further into the room you gain some ability to bring them farther from the side walls. Extreme corner placement is unlikely to give a good in room response, but we can postulate until we're blue in the face. At least Room Optimizer will give you some idea of what to expect at differing positions and even offer some suggestions for best placement. If you are going to the expense of putting in a room, the money spent for the chance to do some acoustic modeling is probably worth it.
There are some classic rules of thum speaker placement methods at
http://www.cardas.com/insights/roomsetup.html
http://www.audioasylum.com/audio/faq/audiophysic.html
http://www.tnt-audio.com/casse/waspe.html
http://www.immediasound.com/Speakersetup.html
to peruse. I don't necessarily espouse any one of them, but they do provide some good reading. I don't think any of them conform to the limitations you are presetting. I list them here just to give you some other approaches.
In my mind, the sound system should be designed to do well for stereo sound reproduction as well as movie sound tracks. Why limit oneself to mere theater sound when you can aim for both?