I am in the process of setting up my Epic 80 and I just wanted to understand the meaning of phase 0 or 180 in sub woofer? The manual says experiment on which one sounds better but I would prefer to understand what I am experimenting on.

I was also somewhat confused with the one coax wire pre-out from my receiver. The other speaker pre-outs have L and R while there is only one sub preout. It was right beside another pre-out labeled center. On the other hand the EP350 has two coax in (L/R). I almost assumed that I should have used the center out for L and the Sub out for R. I decided against it and used a y connector - one from the receiver then split into two for the sub. The question is would it have been devastating if I continued with using the center preout for L and the sub preout for R in the sub?