When I was in college, in the late 70's, I wired each pu of my Jazz bass out separate sides of a stereo jack. I also made a y cable, stereo 1/4 to two mono 1/4. I ran the neck pup clean into the bass input of my traynor, and the bridge went through my little muff and a small stone into the guitar input of the amp. That was some big fun. Splitting you signal can open up a whole new world. I just read about taking a split signal through two envelope filters, one in an up sweep mode and the other in a down sweep mode, the possibilities spiral endlessly............