I spoke with 'Brent' at Axiom a little while ago and he answered a lot of my questions from post #187 above.
[Keep in mind that I'm just passing on what I was told]:
1) According to Brent, the M22s will easily put out 106 db (assuming enough amp power). He said they are still very clear sounding at that level. He said that they are up to THX specs but Axiom (like other mfrs) didn't want to pay the licensing fees because it would increase the cost of their speakers.
2) Ceiling mount is fine.
3) Inverting them is a good idea -- particularly the center speaker, to get the tweeter close to the center of the screen.
4) The L/R should probably also be inverted for a good sound stage, but he said that the main thing was to get the tweeters all on the same plane. So, although it's not ideal, L+R _could_ be mounted 'right side up' with the center speaker inverted if all three tweeters were at the same level.
5) Brent said that ideally the tweeters should be at ear level but angling the speaker cabinet is ok, if necessary. The dispersion angle is 105 degrees, so it may not matter at a listening distance of 10 or 12 feet. He said to try it both ways and see.
He also said essentially, "the more amplifier power, the better", and that the 200 watt max spec is just a 'guideline'. He claimed that Axiom tests their speakers with 800 to 1,000 watt amps cranking heavy metal and they take it. Hard to believe, but I'm just repeating what he said.
I will most likely be suspending all of these speakers from the ceiling. Brent said they have a 1/4-20 threaded insert in the back panel that is designed to allow their wall bracket to be attached without damaging the cabinet. Unfortunately,the wall bracket won't work for a ceiling mount, and (according to Brent) the Axiom _ceiling_ mount won't work either -- apparently it isn't strong enough.
So, question: How to suspend the M22s from the ceiling? It's all wood -- no concerns about finding a stud, etc. I'd like to use the 1/4-20 insert if possible.