Volume 42, Issue 4

Formant frequencies of the semivowels /j/ and /w/ in Amharic, Yoruba and Zuni were measured in three vowel environments. Cross-language differences were found between what are described as the same semivowels, i. e. different languages have different acoustic targets for /j/ and /w/. These cross-language differences in semivowels correlate with cross-language differences in the respective cognate vowels /i/ and /u/. Nonetheless, the semivowels differ in systematic ways from the vowels in directions that make them more ‘consonantal’. These languages also differ in their patterns of coarticulation between semivowels and adjacent vowels. This shows, inter alia, that palatal segments differ from language to language in their degree of resistance to coarticulation. Because of these language-specific coarticulatory patterns, cross-language differences in acoustic targets can only be established after careful consideration of the effect of context.

Quantitative evidence to substantiate accounts of Swahili phonetics is scarce. In this paper, attention is drawn to the particularly complex feature of aspiration. A set of working hypotheses for experimental research are formulated. On the basis of field observations, aspiration is assumed to be operative at several levels of Swahili grammar. Contrary claims are reviewed and discussed in relation to informant selection and control methods for experimental procedures. A digital phonetic data base under current construction is outlined. Speech samples from the data base are used to quantify Swahili aspiration along the voice onset time dimension. The data suggest that the physical manifestation of the aspiration feature is relatively strong in Swahili as compared with Swedish.

A perceptual study of the influence of pitch on the intelligibility of vowels was carried out using a corpus containing all 15 French vowels sung by a professional soprano across her entire voice range. Four untrained subjects underwent identification tests whose results show statistically that vowel intelligibility is inversely proportional to pitch. A perceptual analysis based on confusion matrices revealed that intelligibility drops rapidly starting at the middle register. Classification of the confusions showed that incorrectly identified vowels tend to be confused with [a], most certainly because the shape of the vocal tract when in the upper register corresponds to that of the vowel [a].