This diagram was for illustration/design purposes for the screen wall and stage, not necessary absolute speaker position. In fact, I was thinking of different colors for the proscenium. Grey was one of the options before I went all black.
For actual location, I read here on AVS that the tweeter needs to be at ear level (might have been Dennis or perceived to be Dennis). Sorry, no mags! In my case, it's about a 1/3 of the screen height. Thats what I did right or wrong. Also, I didn't use an AT screen so I had to make a compromise and put the center channel below. Many of the folks here without AT prefer above the screen, but I had no room to do so. I think if I had not been further along at the time, I would had gone SmX and that would helped. It would be helpful if you had a link to the information about your speaker location position so that others might learn from it.
Most rooms have some compromise. My room isn't as big as I would have liked. You have to make trade-offs based on what's more important to you. In my case, it's not just height, but closeness to the wall since I wanted a larger screen. I'm actually very happy the sound of my room. Could it be better? Probably. Could raising the speakers some help? Maybe. I do have the flexibility to move them higher behind the panels, so maybe I'll see if there is a difference.
Thanks for the post.EDIT on 08/12/08:
Adding his construction thread (http://www.avsforum.com/avs-vb/showthread.php?t=995892
) as a "reference" a year after I discovered it.