Originally Posted by sikclown
Is an inch enough space to give the rear port? I don't know the answer, just curious.
The honest answer is no. however, ports are for the sub, not the tweeter, and I generally let the sub do all the bass work on home theatre. HOWEVER, with the X5200W I will be testing that theory and I wanted to leave at least some space off the ceiling for air to not completely screw it all up. My ceilings are only 8 feet tall, so after the 12 inches I'm giving for the length of the speaker there's not a ton of space between that speaker and my ears. I really can't give it the 6 inches Klipsch wants me to give it. When all is said and done it may be slightly more than an inch of clearance, and the good news it that the area between the speaker and the ceiling will be completely free (i.e. not enclosed like a....bookshelf!), so I'm pretty sure the speaker will do ok in the environment I'm putting it in. Irregardless, I will be reporting if I encounter problems with the way it sounds.
Honestly the biggest issue I had was the dispersion angles that Dolby wants...which is 90 degrees from the axis. The RB51's are 90x60.