I'm with Mike, but assume you want a cab either side of the Drummer. Having made up my own I think the speakon can take 4mm cable max, so go for that, tin the ends with solder before screwing down. I also have a heavey duty PA extension cable I use on large stages, 4mm cores the rubber outer sheath is about 10 - 12mm dia, no probs with the sound there. getting a quality cable is the main aim. I used see through flat twin hi-fi cable from Richersounds on my bass cabs. Its oxygen free you can get all sizes and you can buy it by the metre.