Ive got a ten inch subwoofer boxed and everything hooked up to my sony xplode stereo. The problem is i wanna get another sub and on the back of my Stereo theres only 1 RCA Cable input so i can only have 1 sub hooked up, i dont wanna go out and buy another stereo, so is there An adapter or anything that allows my Stereo to run 2 RCA Cables.