Volume 60, Issue 4

Yeyi has the largest known inventory of click sounds in the Bantu language family. It is now entering a moribund state, and this paper documents a variety of acoustic and distributional details of the clicks found in the speech of 13 Yeyi speakers by presenting sound inventories, spectrograms, palatograms, and related acoustic data. The durations of the closure and release phases of the clicks were measured, and an analysis demonstrates that the two duration measures together are statistically able to distinguish the dental, alveolar, palatal, and lateral clicks from one another. A second quantitative study examines the discriminability of the four click places using solely the anterior burst power spectra, as parametrized using the first four spectral moments. The places of articulation are found to be moderately well classified by this means. The patterns of interspeaker variation affecting the clicks are also documented, and these are found to accord rather well with the classification errors made by the optimal classifier using the anterior burst spectra.

The aim of this experiment was to assess empirically listeners’ behaviour in characterising pitch contours with the label pitch register. The motivation for this assessment was initiated by the conflicting use of the term register in speech science and intonology. The findings reported here indicate that pitch register would more appropriately be associated with the position of the low pitch targets and the mean value of the tonal contour. In addition, the importance of the reference frequency (the lowest F₀ of a speaker) and the distance between H and L targets have been found to be weaker than previously assumed.

This case study reports on an acoustic investigation of the motor speech characteristics of a set of young adult male monozygotic (MZ) twins and compares them to those of an age- and sex-matched sibling who participated in the study 2 years later to match for demographic factors. Coarticulation patterns were investigated from read samples of consonant-vowel sequences in monosyllabic words containing a variety of consonants and vowels. This was done by examining F₂ vowel onsets and F₂ vowel targets, plotted as F₂ locus equations. Data were processed for between-sibling differences using a number of statistical tests. Results indicated that the MZ twins displayed F₂ parameters and coarticulation patterns which were more similar than those of their age- and sex-matched sibling. The results of this case study therefore suggest that acoustic phonetic parameters used to index coarticulation patterns have the potential to profile some of the similarities and differences in the speech characteristics of genetically related individuals.