In reply to:

i always found that i get the best soundstage when the tweeters are at the same height,and the height is not a problem because my seat is 22' away.


Oh... Poor rcvecc! Are you watching that tiny little TV screen from whopping 22' away? We watch a 120" diagonal from 13' away -- and believe or not, that ratio is pretty close to the THX-Home recommended specs.

Time for you to get a front projector, isn't it?