Journal Article
A Linear Theory of Phonograph Playback
Journal of the Audio Engineering Society · Volume 19 · Issue 2 · pp. 94–100 · February 1971
Abstract
Previous theories of phonograph playback have been based on the convenient but physically inappropriate assumption that groove deformation can be described using classical elasticity theory. In the present analysis, in contrast, the exact nature of the groove deformation is left unspecified. The mechanical frequency-response function is shown to be uniquely factorable into two transfer functions; a pickup function and a scanning function. The pickup function is calculated for an ideal lumped-element pickup. Also, the magnitude of the average groove deformation that is necessary for maintaining stylus-groove contact continuously is calculated for the case of an ideal recording that contains a pure tone whose frequency is near or above the stylus-groove resonance frequency but low enough that scanning loss can be neglected.
