I put a mtx xt110p (10" powered sub w/passive radiator) in my 2011 2dr. Sounds great but it has 2 sets of inputs for front and rear RCA's. With this being a sub only why the need for 2 RCA'S? I have it hooked up to a JVC nt3hdt head unit and ran only 1 set of RCA's from the JVC rear output to mtx rear input. Am I missing something by not hooking up another set or can I just split it back at the sub?