Doug,
I have subwoofer On/Off. That is it.
After more research here is my decision and my reasoning. 1.Mains>Large. 2.Sub>On. 3.Center and Surround>Normal. 4.Sub Crossover> 80hz.
Reasoning: My sub is small. Also I can't shut my sub crossover off, so I set it to the highest setting which is 80hz. If I had the mains set to Normal then at the crossover for the receiver everything below 100 would go (not a brick wall)to the sub as a low pass. The sub crossover will block some of the frequencies between 100-80 hz. With the Large setting all of the bass 80-100 blocked at the sub will be redirected to the mains. I still get the LFE through the sub, atleast anything below 80hz. (brick wall) I have been lead to believe that a sub can reproduce the very low LFE better than any mains. Even a cheap sub at, say 20-30 hz, is better than a good set of mains at producing this band. Please evaluate my logic. Thanks