Document Type
Article
Publication Date
4-14-2008
Journal / Book Title
The Journal of the Acoustical Society of America
Abstract
Nonlinear source-filter coupling has been demonstrated in computer simulations, in excised larynx experiments, and in physical models, but not in a consistent and unequivocal way in natural human phonations. Eighteen subjects (nine adult males and nine adult females) performed three vocal exercises that represented a combination of various fundamental frequency and formant glides. The goal of this study was to pinpoint the proportion of source instabilities that are due to nonlinear source-tract coupling. It was hypothesized that vocal fold vibration is maximally destabilized when F0 crosses F1, where the acoustic load changes dramatically. A companion paper provides the theoretical underpinnings. Expected manifestations of a source-filter interaction were sudden frequency jumps, subharmonic generation, or chaotic vocal fold vibrations that coincide with F0 - F1 crossovers. Results indicated that the bifurcations occur more often in phonations with F0 - F1 crossovers, suggesting that nonlinear source-filter coupling is partly responsible for source instabilities. Furthermore it was observed that male subjects show more bifurcations in phonations with F0 - F1 crossovers, presumably because in normal speech they are less likely to encounter these crossovers as much as females and hence have less practice in suppressing unwanted instabilities.
DOI
10.1121/1.2832339
Montclair State University Digital Commons Citation
Titze, Ingo; Riede, Tobias; and Popolo, Peter, "Nonlinear Source-Filter Coupling in Phonation: Vocal Exercises" (2008). Department of Communication Sciences and Disorders Faculty Scholarship and Creative Works. 75.
https://digitalcommons.montclair.edu/communcsci-disorders-facpubs/75
Published Citation
Titze, I., Riede, T., & Popolo, P. (2008). Nonlinear source–filter coupling in phonation: Vocal exercises. The Journal of the Acoustical Society of America, 123(4), 1902-1915.