Wow, this is an old thread! I am getting much closer to needing the in-ceiling speakers for my system. It has been a long, long process!

Budman,

For ht use with the x-over set at 80, I'm not sure you would notice a difference between the 6.5" and 8" speaker. However for audio use, I would think you would want the bigger speaker. Another thing I noticed about the two though, is that the 8" has a 1" tweeter and this may (I'm guessing here) match the ascends a little more closely. Unfortunately these type of speakers are very hard to audition... []

I am leaning towards chambered speakers due to the construction of my ceiling. The floor joists are not solid wood, they used open trusses and I don't want the sound to travel all throughout the house.

Please let use know what you decide.

Derek