So far, no one has explained just how this "pre echo" signal could be subsequently produced by deformation of the uncut vinyl, into a groove just cut, and "superimposed" on that already-cut groove with the ACCURACY of an actual cut groove, necessary to be able to identify the resulting signal (traced by the stylus,) as not only containing some kind of an "echo", but having the fidelity necessary to identify the original music signal that gave rise to it.
As for CDs, I agree with eldartford, never heard even an AAD CD with a tape print-through signal between tracks.
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