I recently purchased another sub. I am using a y connection out of my receiver (which has only one sub output)and then running two lengths of rca wire to each sub in separate areas of the room. Each sub is self powered. One of the subs is a JBL, and I use another y connection to input two jacks into it (seems to sound better this way). With the smaller yamaha I just connect the one rca jack. Does this sound about right? I've never had a second sub connected before. The receiver is a Marantz.