just aquired the above speakers & would like advice on placement. I have a large(ish) size room with a high slanted roof(left to right). I had planned to put the speakers on the back wall about 15" up in the air(above the curtain rail), cause my sofa is up against the back wall. Is there any recommended location for these type of speakers? Rest of setup: pioneer 504/868/812amp speakers: mission 733i*2 front/mission 733 centre/rel strata III sub.