[aresh]

when i had all 4 wires plugged in, my sub would never hit hard and they would almost always blow or my amp would over heat. The reasoning i have, your getting signal, a low pass signal from the two subs underneath, just one signal from one sub would give you a clear signal rather than having two signal pushed into one sub. the way i have mine setup is, pick any sub you want signal from and cut the other sub out. EX. right l7 subwoofer, right postive and right negative will go into your lci.