We are remodeling a wall that had a TV cubby made for a 36 inch tube TV, and it was plenty deep to allow my Polk CS400i to sit on top. I'm having trouble making this somewhat large center channel fit. 9"h x 19"w x 14 inches deep. the new plan centers the fireplace on this wall and above the mantel will be the location for the flat panel. I had planned to flush mount the center channel above the TV but today after tearing out sheetrock I found a 4x16 inch header that makes the option not as viable. Can I flush mount the center channel and build it into the mantel without ruining the sound? There is a port on the back of the speaker. If I put this in a "box" won't it sound wrong? Can I mount it all the way up at the top of the ceiling, say 8.5 feet up slightly angled down and have it sound OK? Again will it sound wrong it its mostly surrounded by drywall? I guess an other option is to find a different (smaller) center to match my front speakers (polk RTi70s) but I really like the overall sound these three speakers present. Thoughts?