For anyone who's searching on the Bybee topic, I can report on the Bybee filters as I have installed them on my home theater system surround sound system recently. They do work, no doubt about it. One large one was first put on the positive input of my center channel speaker and it is like turning the volume up on the center channel only and also increasing the clarity. I also installed a second small slipstream bybee on my DIY noise filter based on the Jon Risch design, and it further improved the sound, much more than the first one. On DVD's sounds not previously distinguishable before are clearly heard now - low level voices, background sounds, low level notes, etc. It is like someone turned the volume up on the surround sound volume. Also notes seem to last longer before fading, especially high notes. They were worth it to me. They work and are not snake oil, to be sure.