Ok, so when you don't connect a center channel then the reciever automatically splits the center channel and sends it to the left and right mains? I wasn't sure if it would do that or not. I installed a 5.1 channel head unit into my car. And before I added a center speaker, movies I'd play on there had no dialog except for a very, very faint echo in the left and right front speakers. When I hooked up the center speaker, I had dialog.

My Stuff :

M80's
QS8's
VP150
EP800
Denon 4802
Emotiva XPA-3
Samsung BD-P3600
Sharp 65 Inch Aquos LCD