Tom says, I've used all of these types of things, and they work. I use Bybees, and they work nicely. I use power conditioning and it works. I use decent IC's and Speaker Cables , and they work well. I think a combination of things is the way to go. If you have a real problem, address it as best you can. I use Bybees at the speakers, and battery power for the mains. I don't have an RF problem, so I use unshielded IC's. I have no AC wiring or power in my house, except for the high voltage section of my tube preamp. I have DC lights, DC refrigerator, no TV, and DC everything else. I am 400 feet from the nearest power lines, and am not connected to it. The stray fields in my house are as low as it can get. So, I am adressing the issue from as many directions as possible. No mains power or fields. DC battery power wherever possible. Less offensive appliances in the house. And I still have Bybees on the speakers, and they still help. Do whatever you can, and you'll get better results out the speaker. But be sure that it really does something. Don't buy snake oil.