I think I might've not explained it properly: the amp doesn't have a sub out. It does however have two speaker outs (for A/B testing, I presume). My question is whether I should connect the sub to the A out (which my speakers use) or the B out which is currently unused.
My old 80's amp has two different speaker outputs (but only two channels - the two outputs are identical). It doesn't have a sub output, so I will need to wire it up either using the unused speaker output or by adding more wires from the speakers' inputs. What would be better? Does it matter...