Speaker sex identification utilizing a constant laryngeal source

Abstract

It has been demonstrated that the sex of speakers can be reliably and accurately identified in the absence of idiosyncratic glottal wave forms. This finding led to the hypothesis that there are other sex-related differences in the supraglottal vocal tract which produce discriminable acoustic differences in the speech signal. As a test of this hypothesis, six males and six females counted to ten and read the second sentence of the 'Rainbow Passage', with a closed glottis, while using an electronic artificial larynx (fundamental frequency 120 Hz). The vocalizations were tape-recorded, randomized and played to 30 listeners who were asked to determine the speakers' sex. Later, the vocalizations were subjected to a sound spectrum analysis. Results indicated that male voices with speech spectra shifted toward the lower frequencies were identified above chance as were female voices with speech spectra shifted toward the higher frequencies. Speakers, whose energy concentrations were centralized, were most often confused. These results confirm the hypothesis that sex-related supraglottal vocal tract characteristics (potentially vocal tract size and shape) can play a major role in the identification of a speaker's sex.