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?
Getting great feedback, but with all the recommendations, which setup will get the best out of the subs and ultimately the system in general? Connecting subs using the same 8 ohm taps as my current speaker connection seems to be the easiest setup if it gets the best out of the subwoofers. Granted I haven't 100% decided which subs, but leaning towards the SVS PB/SB-2000's..
"They" say the best integration of subs with your main speakers are obtained by using high level inputs. The signal to your sub is the same as to your speakers, having gone through the same signal path.

Maybe somebody else can support or refute this. I do know that manufacturers would not incur the added cost of high level inputs on the higher end subs without a justification.

I would guess XLRs would be the next best path, RCA last. 

In this hobby there will always be those that vehemently advocate or refute damn near anything without evidence, so make your own judgements and don't look back.

I use the high level inputs on my RELs, and am very satisfied with the results. Would I be just as satisfied with using XLRs? probably.
If your subs are the active type, read powered by it own internal amp, which the SVS PB/SB-2000’s seem to be, I would run your subs directly from additional outs of the preamp...

Why taint that tubed goodness in the signal chain with an additional SS amp? The SVS subs have a class D internal amp...