Document Type : Research Paper
Authors
1 Assistant Professor of Linguistics, University of Isfahan, Isfahan, Iran.
2 Associate Professor of Linguistics, University of Isfahan, Isfahan, Iran.
Abstract
Rhythmic characteristics of speech based on consonantal and vocalic intervals as well as syllabic intervals vary between speakers of the same language. Nonetheless, the rhythmicity of a speech signal is not solely dependent on the durational variability of phonetic intervals but it is also associated with the variability of the intensity patterns as well. Acoustic parameter of intensity is largely determined by the articulatory behaviors of the speech organs such as lip movement or mouth aperture. Therefore, it is plausible that speaker idiosyncrasy in movement of speech articulators and anatomical differences in individual’s vocal tracts may influence the energy distribution across a speech signal which subsequently leads to the variability in the values of the intensity measures. Using experimental phonetics tools and from an explicitly speaker-specific perspective, the present research attempts to explore potential speaker-specific acoustic parameters of speech rhythm which are extracted from the intensity contours across Persian speakers. This research aims to discover whether intensity-based measures of speech rhythm are able to discriminate between speakers in Persian. Two types of acoustic rhythmic measures based on the mean syllable intensity (stdevM, varcoM, rPVIm, nPVIm) and peak syllable intensity (stdevP, varcoP, rPVIp, nPVIp)) were selected for this study. Speech data from 12 Persian male speakers were recorded non-contemporaneously in laboratory environment on two different occasions separated by one to two weeks. Speech tokens were acoustically measured with PRAAT version 5.2.34 and statistical analyses were carried out with SPSS version 21 and R version 3.3.3. Results of the study indicated that speech rhythm measures based on intensity fluctuations play an important role in between-speaker rhythmic variability. In addition, discriminatory power of intensity-based measures is not affected by the language-dependent characteristics of Persian. The results also showed that the peak syllable intensity measures carry more speaker-specific information compared to the mean syllable intensity measures
Keywords
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