Here is a useful Dolby diagram:
http://dolby.custhelp.com/cgi-bin/do...p_sid=bZ5Vm*Hg
If the link doesn't work, visit
http://www.dolby.com, select Dolby Knowledgebase and it should be the #1 subject.
An excerpt from an article on Home Theater Mag's web site (
http://www.hometheatermag.com/showarchives.cgi?116:5):
"THX has developed what they feel is a single approach that allows for simpler system operation and better performance in all cases. For one, THX recommends a 7.1 speaker layout that still includes two dipole speakers to the sides of the listener but recommends two closely spaced, direct-radiating speakers in the back. THX prefers two monopole back speakers in order to preserve the discrete surrounds of multichannel music and EX/ES soundtracks. The close proximity of the two speakers also preserves a stable central image for both on- and off-axis listeners, while the THX processor applies new spacializing effects (called ASA, for Advanced Speaker Array) to create a wider soundstage than the placement would suggest. "
So the key is keeping the rear surrounds closer than your current surrounds, within 60-90 degrees from the listening position.
As for the mains, do you have dipole surrounds now? I have a pair of bipole/dipole CSW S200 surrounds that I like very very much:
http://www.hifi.com/store/category.c...xxx&type=store
For your rear surrounds, I'd think mounting them 9'6" high is not a problem. I've not seen whole enclosure pivoting speakers, only in-wall speakers with pivoting tweeters, such as:
http://www.hifi.com/store/category.c...2wh&type=store
You can paint those in-walls to match.
Sean.