Synthetic Sound on Film
Robert Edward Lewis, Norman McLaren · Journal of the Society of Motion Picture Engineers · 1948
An analysis of both hand-drawn and machine-made sound tracks is presented together with methods. — Of fundamental importance is the fact that synthetic sound tracks for the first time enable a composer to hear his composition as written rather than through artists' interpretation. — Three basic methods are presented: (1) hand drawing directly on the film, (2) frame-by-frame photography of drawings and patterns, and (3) mechanical generation by machines, such as the harmonic integraph, which are coupled to a variable-area or -density modulator registering on the film.