Formants of children, women, and men: The effects of vocal intensity variation

The purpose of this study was to investigate the formant frequencies and am plitudes of a wide age range of children and one group of adults at three s ound pressure levels (SPLs). Subjects were ten females and ten males in the following age groups tin years): 4, 6, 8, 10, 12, 14, 16, 18, and adults. A sustained /a/ was produced three times by each subject. Formant: frequenc ies were obtained using linear predictive coding analysis. Formant amplitud es were measured from the highest amplitude harmonic in the area of each fo rmant. In addition to following established trends previously published in other studies, it was hypothesized that the first formant frequency would i ncrease with increasing intensity, that females would have higher formant f requencies than same aged males, and that women and children would have red uced formant amplitudes as compared to men. It was found that first formant frequency increased with intensity and changed as a function of age and se x. Second and third formant frequencies changed with age and sex. Formant a mplitudes followed the trends set by the SPL differences and did not change as a function of age and sex. Results are discussed in terms of anatomic d ifferences and SPL. (C) 1999 Acoustical Society of America. [S001-4966(99)0 2109-8].