I did a little quick research and it appears that CD players use photon lasers. Photons have no charge and therefore would not be effected by a magnetic field.
Can someone explain what the mechanism is for magnetic ink to influence the playback of a CD in a negative way, or at all? I would guess the ink explaination came up as a response to people first becoming skeptical of the product as it was first advertised.
07-09-14: Mceljo
Mceljo,
Quote from link.
"Now, the CD rotates pretty fast (200 to 500 rpm), and any ferrous material will gradually become slightly magnetized over time if it is rapidly moving in a magnetic field (the earth's magnetic field will do, but there are doubtless other magnetic fields as well within a CD player). All right, so we have a CD with some slightly magnetized pieces of ink, spinning around inside your CD player. How does that cause contaminating noise in your music?
Let's assume that the brown pigment in brown ink is ferrous, and let's assume that some small lettering on the CD label is printed in brown ink. Let's assume that there are about 50 letters in the small lettering, which means that there are about 100 vertical ferrous bar magnets (for example, the letter H has two vertical bars), rotating around with the CD. These rotating bar magnets are putting an electromagnetic noise field into the space and air inside your CD player. If the CD is rotating at 8 Hz (480 rpm), and there are 100 discrete bar magnets going around at 8 Hz, then they are putting out noise with a fundamental at 800 Hz, together with all kinds of overtones spread upward throughout the rest of the musical spectrum (if we were to assume the bar magnets were purely rectangular and put out noise that looks like a square wave, there would be overtones at 2400 Hz, 4000 Hz, 5600 Hz, etc.).
You can see that this contaminating noise thrown into the air is rich in high frequency spectral content, so it would be most destructive of music's higher frequencies and of singular, non-repeating musical transients, if it were to somehow interfere with the music signal inside your CD player. And, if a CD treatment like the Furutech could reduce this high frequency contaminating noise, then we would expect to hear the sonic improvements being most dramatic for music's trebles and for its singular transients - which is exactly what we do hear.
Given that this noisy electromagnetic field is radiating into the space and air inside your CD player, how could it come to actually contaminate your music? After all, your music signal is safely traveling inside the conducting wires of the CD player's circuitry, isn't it? So who cares if there's spurious electromagnetic noise in the air outside these wires, right?
Well, it turns out that electromagnetic fields in the space and air just outside your CD player's wiring can also penetrate into that wiring, so if that field comprises contaminating noise, then that noise can add to or interfere with the signals in your CD player's wiring. The analog circuitry in your CD player is certainly vulnerable to signal degradation by interference from noise, but so also is all the digital circuitry in your CD player. Why? First, that so-called digital circuitry is actually analog circuitry, operating with precise thresholds and precise currents, whose level and/or precise timing can be contaminated, degraded, or made less determinate by noise. Second, it is now widely recognized that merely adding noise to a digital signal in your CD player can worsen jitter (by making thresholds more temporally indeterminate), which in turn worsens distortion of your music when that timing indeterminacy reaches your DAC chip. If the interfering noise has high frequency content, then this can cause high frequency jitter, which is especially destructive of music's higher frequencies, causing smearing kinds of distortion (from FM distortion sidebands spread over a wide and high frequency range).
Furthermore, it turns out that the desired signals running around in the wiring of your CD player are not really traveling inside the wires, but instead are actually traveling as electromagnetic fields in the space and air outside those wires - in the very same space and air also occupied by the noisy electromagnetic field from those spinning magnets on the CD. Since the desired CD player signals, representing your music, and the noise from the spinning CD magnets are both mixing it up in the same space and air, naturally there is cross contamination.
Similar considerations would apply to any ferrous impurities in the aluminum deposited on the CD as its reflective layer."
http://www.iar-80.com/page53.html