I'm in the process of setting up home theater and need advice with the cable connections from the elite vsx82txs to the emotiva mps-1. The pioneer has pre-outs (unbalanced: l/r front, center, sub, l/r surround, l/r surround back, l/r single) for connecting to an external amp. The emotiva has a single unbalanced input or a single balanced input for each channel. How do I add an extra center channel? Does a cable with unbalanced and balanced connections exist? Is there any advantage?