The Japanese have a ultra high speed train that is suspended by magnetic repulsion. The material that spins is aluminum. Although the material is non magnetic, the explanation is that the material sees its reflection in the high speed wave and creates a magnetic field that is near zero friction and strong enough to suspend the train. I am probably not explaining it well, and if there is any real interest on this subject, there are probably sites on the internet that cover it. The CD spins at well over 600 RPM, and I admit that I do not know if this could create any magnetic reflections or even if this particular explanation has anything at all to do with the subject we are on. I do know is that there are a number of people who I respect that say that using a demagnetizer improved the sound of their CD's. There was a time when I was told that the power cables running to your equipment could effect the sound, and I had a hard time believing them. Luckily I experimented and no longer own any factory supplied power cords. The point here is to discover what works, if this tweak does improve sound it may be worth it to him. Anyway, Hornby (the poster), probably does not care why it works or if any of us are correct in our theories. All that matters is that it is an inexpensive experiment, not much worse than some bad choices at the local music store in software purchases, and it might improve his entire library. One last thing......several years ago when I owned a Krell MD 10 CD transport, our group was testing digital sources, comparing Krell to Wadia and Theta. We had tried several types of interconnect and different feet, and we came to the stage where we adding weights to the top of the players. During one experiment I went back to play an LP and put the record jacket on top of the Krell after I removed the weight. There was an amazing improvement in the Krell when we returned to play it again, and we were totally puzzled by this before finding the solution. My room lighting is primarily halogen spots and I had installed photographic gels to correct the color temperature so LP's would look a more natural color. The top of the Krell is Plexiglas and the combined colors were causing errors in the laser. I reported this to Krell, and after they tested, they provided a modification where this unit was shielded from extraneous light to avoid this error. I know this is not related to magnetics, a laser is light and the error was caused by light, but there are many things that seem implausible at a given time that later have an explanation. As I said before, I am an experimenter and music lover, not an engineer. If this works for this guy, for whatever the reason, I hope he reports his findings here so someone else may benefit. I don't think making light of this posters enthusiasm to experiment is a very good source of entertainment.