OK guys.....I hooked the X-Sub to my Nad 352 integrated amp by using the pre-out L and R on the amp to the X-Sub L and R. Nothing popped or anything significant, so I am assuming this is working. I have never used a sub before and this is strictly a two channel set-up. I am about 12-15 feet away from the Salk's. How do I know this is working? I know this is a strange question. I placed my hand under the sub {I believe they call this down-firing?} because the woofer is on the bottom. When I put on Babylon Sisters by Steely Dan, you could feel the woofer moving. I have the crossover set to 70-80 on the sub and the volume at about 5. The phase is on zero. I know the sub was working. But, I couldn't really tell without placing my hand there. I have the sub close to a side wall right now. I haven't really done much moving of it because of the power cord length and also cable length. I don't have any measuring tools either for sound. I know that could be a problem. Again, since this is a down firing sub does it matter it is close to the side wall? It is facing across the face of the speakers right now. I can move it to the side of the speakers eventually. It sounds like things are meshing with the sound. I just wanted to see if there were any problems with the X-Sub and it turning on OK. There have been a few issues with that on the AVS123 forum. Am I starting off OK or am I doing something wrong so far? I never really have read how far down the Salks would reach so the crossover is a guess from what I've read on their forums by some people using subs. Of course, I'm not sure they have hooked theirs up like mine either.By the way, Babylon Sisters sounded great. The kids and wife came home so I haven't had much time to experiment.