yeah...I've had these ProMedia Ultra's since fall of 2004 and they are STILL KICKIN BUTT! Anyways, Ever since then I always wanted to add another sub. So this is a good question. I've read somewhere in these forums that a member here has a KSW 10 hooked up to his. However, when I looked at the back connections of the KSW10 there are 2 RCA inputs. R/L. So..if we or I were to hook this Sub up to our Prom Media's SWS Link, which RCA 'Line-in' do we use. If it doesn't matter then would I be correct on saying that I/we could use any sub that has a RCA input? (regardless if there are 2)