agreed, you dont need a special cable to use a regular cab...
if you are considering wishing to use the biamp feature, a quick look at the amp highlights says that the tweeter output has a built in high pass filter of 5kHz... so your crossover frequency in the cab would need to be real close to that to avoid gaps in response..
given a regular speakon cable also works on the head, i think the treble control knob looks more attractive than biamping for a non gk cab
Genz-Benz #429, G&L #502, Ibanez #1034, Mediocre Bassist #883
Genz-Benz Streamliner 900 & Uber Quad, TC BG250