Fourier Analysis and Vowel Curves

Abstract

ATTEMPTS were made recently to apply the Fourier harmonic analysis to a collection of very large vowel curves traced off from a gramophone record through the courtesy of the Gramophone Company (His Master's Voice) of Hayes. One such wave in the actual size is reproduced in Fig. 1. The wave was first analysed by measuring 24 ordinates (12 harmonies). When a new curve was constructed from the results it showed scarcely the faintest resemblance to the original. The most important characteristics did not appear at all, and all the characteristics shown were erroneous. Owing to the small vibrations, at least 200 ordinates would have to be employed in order to produce any resemblance. This would require that number of schedules. At present the highest number for which schedules have been drawn up is 72 (published in my “Studies of Speech Curves”, Carnegie Institution Publication No. 44). The work with 150 ordinates for a single wave would keep a person busy for several months.