Summary: Academic Article
Publicado por Pedro Pablo Escalante | | Posted On domingo, 27 de febrero de 2011 at 13:18
Two processes affect the characteristics of vowels; phonological and phonetic vowel reduction. The former applies to unstressed vowels and the latter applies to all vowels and it causes by fast speech rates, context and lack of stress. The changes in stress and in rate of speech on the acoustic characteristics of American English vowels were examined. Four male and four female natives produced these vowels in two contexts. Measurements of duration and frequency showed the vary tempo and stress. The change in stress on vowel duration was larger than in tempo. The vowel portion was analyzed; formant tracks were plotted in an auditory- perceptual space. These plots determined the part of the utterance considered its steady state. The distance of these data points from the point representing the acoustic characteristics of a vowel was used to determine the magnitude of phonetic vowel reduction caused by faster tempo and less stress. The results indicate that tempo and stress may not have influence on the distances of individual vowels from the neutral point, however the size of the vowel space was affected. It was largest for the slow stressed condition and smallest for the fast unstressed condition. (195)