Thanks a lot for your help, EKF. Oddly, lack of bass is not why I'm asking about the subwoofer. The CF4's easily put out plentiful bass on their own in my setup, so much that it can be difficult to get a handle on. Not only do I have to consider imaging and soundstage when placing the speakers, but also the occasionally overwhelming low-end. I was going to try the sub because I figured I could place the speakers where they image the best and then worry about the subs proximity to walls etc... kind of a divide and conquer strategy (my pervious cornwalls always just sounded best in the corners facing 45 degrees out, easy peasy). Concerning the amp, I've also got a Crown XLS1502 300 watt per channel power amp that I've tried. The bass might be a little better with it but the entire presentation just falls completely flat. The music is not engaging at all. I know a lot of budget audiophile guys covet these crown amps for planars and other hard to push speakers but, in my setup, the Sony sounds startlingly better. As for modern subs, I'm a big klipsch fan, any recommendations from their current line that would be comparable/better than the SW15ii?