Are the preamp outs and poweramp inputs balanced or unbalanced? I have a PL3000 preamp and a pair of PL400 poweramps. I want to add a crossover between them to drive one PL400 for the JBLs (psudo L-100s) and the other PL400 to drive the subs.

I'm trying to decide upon a crossover, but need to determine whether or not I need unbalanced input/output.