Just auditioned a total HTR 7000 system and it sounded great so I picked up a pair for surround duties in my 5.1 system. These will be installed in a rather large great room that also shares space with our kitchen: 23' deep x 48' wide with 12' ceilings. Needless to say, I can place the surrounds as wide as optimal. What would be optimal though? Per the instructions, I plan to place them in-line with the seating location or slightly behind and aimed at the seating location. The instructions are fairly vague after that. Am I correct in believing the drivers have 30 degree offset from the ceiling and have 60 degree dispersion angle? I've done some calculations based on these, but wanted to get your thoughts. Thanks!

Yes, 30 degree offset from ceiling, which helps to cast the image in front rather than from above, with proper ceiling height and listening distance. For a 5.1 system, in Dolby's new thinking, you want to place the surrounds wide left and right and behind the listeners. (As opposed to Dolby's old thinking, which surrounds should be on the side - which they now only recommend in a 7.1 configuration.) We would suggest placing them wide spaced behind the listener and pointed towards the center listening position.

Great - thanks for the insight. I'll go with that setup.