Quote Originally Posted by J Henry View Post
My application is for home hi-fi music listening. My room is 9m x 6m x 2.7m high. I usually sit about 6 m from the speakers with the speakers placed on the 6m wall.
OK, assuming the speakers are ~backed up against the wall, then a ~4.076 m listening distance may prove a little smoother overall. Speakers then would be about this far apart and ideally would be offset along the wall to average out any sidewall eigenmodes (standing waves), so ideally the listening 'sweet spot' would shift also.

Anyway, lacking sufficient geometry skills to quickly calculate desirable horn patterns, I'll leave you to either calculate them or do as I do and make a scale drawing of the room and with compass and straightedge, find what speaker toe-in and arc patterns cover/overlap the listening position without any first reflections in front of the listening position and let this guide your selection rather than size, long/short throw, etc..

GM