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In Reply to: Bedini - snake oil?? posted by John C. - Aussie on May 23, 2005 at 16:36:58:
A spinning magnet in the vacinty of wire is a dynamo - therefore a CD that has become magnetic for whatever reason will generate a certain amount of current in the components it is spinning near. Reduce or eliminate the magnetic quality of the disk and you reduce the amount of spurious current generated - not exactly rocket science.
Follow Ups:
since when is a cd a spinning magnet?
Since they were given a metalic coating on which to etch the 1's and 0's
Yes, but itS aluminum. Ever see a magnat that attracts aluminum?
(yes i know there is also para- and dia-magnetism, but does that have any effect in a optical pickup system?)
Aluminium is insignificantly magnetic - that is not the same as non magnetic - in the rarified world of Hi-fi this is enough to create an effect - in reality it probably has an insignificant effect. CD demagnetizers are known gadgets though - like green pens and cryo treatment.
The truth of the matter is that polarizable nuclei are random in the normal state. It takes a high and focused magnetic field (in the Tesla range) to produce a net magnetic vector that is significant. Then a RF pulse must be generated to flip the nuclei 90 degrees or somewhere there abouts or there is no "relaxation" time. To detect that relaxation time there must be a resonant antenna at a frequency satisfying the Lamor equation for nuclear magnetic resonance depending on the spin of the particular nucleus. This frequency varies from element to element. Such an antenna will detect a very small signal from the spinning precessing nuclear moment. I highly doubt this can be measured on scientific instruments at audio frequencies or perceptible to the human ear. A spinning conductive medium such as a CD does not a nuclear magnetic resonant event make. Coherence of the laser and its ability to reads ones and zeros, sampling rate, quantization error, filters, quality of critical components, and the system the converted bit-stream are connected to have infinitely more bearing on the quality of sound. Please, lets stick to physics first and subjective opinions second without getting too crazy.
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