David: There seems to be some support for the Asylum Power Cords, which I believe are based on a Bob Crump/TG Audio design and are fairly inexpensive. One thing you might try first is putting a low frequency ferrite clamp around your current cord near where it attaches to the component (assuming you can find the right size one)--they should be fairly cheap. I did this on a captive power cord from one of my components and was very surprised to hear a small but noticeable improvement in dynamics and soundstaging (more low level detail, maybe?). If you look at the new Siltech power cords, it looks like they've got a pair of ferrites under all the sheathing, so maybe this is a low cost way to go. Hey, it can't cost too much to try.
