ABSTRACT
A major challenge to all forms of sound recording has been to establish the optimal and agreed-upon speed of the medium as it spins on a turntable, turns on a mandrel, or passes a given point. A speed that is too slow will result in unacceptable distortion products and one that is too quick will use up the recording surface in a short time. Another problem with analog systems is ensuring that the play-back speed is exactly the same as the recording speed. If it is not there will be a change in musical pitch.
