Captain~
I am in the same boat as you and I have had my 863 for a while now.
Finally catching on though...
I have all my speakers set to small
My LFE is set to Sub
I have my sub crossover up all the way and my reciever crossed at 110 0r 120 ?
I also just went through and turned the Db up on the reciever for the sub from -2.5 or -3 to 2.5 and it made a huge difference.
dont get me wrong, I am by no means well versed in this stuff... but if you have any other guinea pig questions let me know... chances are I have been there and tried it and have still not got it right so we might be able to help each other out
Cheers