re: First, my amp only has a single pair of outputs for each channel, so a shotgun cable would be my best option, or two cables, one banana and one spades.
I get it. My old cables for my 2CEs were true biwires with 4 separate terminated spade ends on the speaker end, and on the amp end they were merged 2 into 1, so I only had one pair of spades (pos/neg) for each channel at the amp binding post.
My new cables are true biwires, 2 separate much heavier, less flexible cables for each channel, At the amp end, one cable has spades, and the other bananas, and my binding posts accommodate both. So—easy to solve. I could not merge the two cables into one pair of spades.
My next speakers, if I replace these (doubtful, unless I go to stand mount monitors), will hopefully not require biwires, but from a cost standpoint.

