How to connect C2500, MC501 and Two Subs

I read somewhere you could connect subs from the MC501’s RCA interconnects even though the amps XLR’s are being used to connect to the C2500 preamp? Is this possible? I’m trying to save money, assuming the subs will sound great next to each amp, by not paying for longer XLR or RCA cables. So is the above correct, or?