I am trying to figure out how to set my Receiver to get the best sound out of it, and am hoping some other 989 owners can help me out.I have a couple of questions. I am running two cables from the sub outs on the receiver. What are the advantages/disadvantages of each? Does anyone have the ver2 upgrade, if so, is it worth it or not? Also, how and why would I hook up power amps to this unit?