Abstract
In common with other aspects of human behaviour, there has been an increasing research interest in the voice, particularly in relation to the production of voiced sounds in speech and, to a lesser extent, in singing. There is substantial knowledge of the structure and function of the vocal system. This knowledge, however, is chiefly located within the voice acoustics literature which has focused on adult subjects who have been predominantly male. Where children’s voices have been studied, the analysis methods adopted have been, by necessity, those designed for use with men’s voices. The present research outlines the current knowledge of the development of vocal structures through childhood and adolescence into adulthood, and highlights some of the problems associated with attempting standard acoustic measurements with children’s voices. Three experiments are reported using the speaking and singing voices of 10- and 11-year-old children. A principal aim was to provide a reliable and valid description of children’s voice characteristics by investigating the spectrum effects of loudness variation, voice source characteristics, and vowel formant frequencies. Standard acoustic and aerodynamic methods of measurement were modified, using carefully designed research procedures, in order to circumvent the problems of measurement. Experienced singers were chosen to allow for control of such acoustic variables as loudness and pitch. The findings from these investigations, and the sex-effects apparent in the data, are discussed in light of previously reported results derived from studies of adults and children. The results showed that, whilst there were some similarities, these children’s voices functioned differently to adults’ voices. Also, sex differences were apparent which differed from previous findings for adults. The present findings were, in general, similar to those previously reported for untrained children’s voices. Thus children’s voice characteristics can be more conveniently derived from singer subjects with their greater skill in independent control of pitch and loudness.