Some acoustical properties of diphthongs

Abstract

One approach to describing diphthongs is to consider them as consisting of a steady‐state nucleus and a glide toward another steady‐state segment. This study evaluates this approach when sources of acoustic variation (change of speaker, stress, and rate) are introduced. In a preliminary study, four speakers of Midwestern American English were recorded producing diphthongs in isolation and in the context /K_T/. On the basis of the first three formants, diphthongs can indeed be characterized in terms of two kinds of spectrally defined states, steady‐state and glide. There is, however, variation in the number and order of these states for particular diphthongs. Plots of these spectral patterns in an auditory‐perceptual space [J. D. Miller, J. Acoust. Soc. Am. 85, 2114–2134 (1989)] suggested that diphthongs can be differentiated by a combination of distinctive nucleus zones and angular movements within the space. Productions by two speakers of a carrier sentence containing diphthongs under varied stress and rate conditions are being analyzed. Results will be used to evaluate the usefulness of the descriptive scheme noted above and the ability of the auditory‐perceptual space to capture differences between diphthongs. Results of this evaluation, in addition to durational measurements of individual diphthongs and their component segments, will be reported. [Work supported by NINCDS.]