LAUSR

In the classic source-filter theory, sound is produced at the glottis by a process known as flow modulation; in this case, “flow” specifically refers to the flow rate (Q) produced at the glottal exit during the phonation cycle. Flow modulation refers to the fact that Q is changing as the glottis opens and closes dQ/dt. Although dQ/dt is constantly changing from glottal opening and closing, the greatest rate of change happens during the latter part of closing, when Q rapidly decreases. This rapid deceleration is quantified by the maximum flow declination rate (MFDR). MFDR has been shown to highly correlate with acoustic intensity (loudness). The aim of this study is to measure changes in Q and the acoustic energy in a vibrating canine larynx model as a function of subglottal pressure and vocal tract constriction. Volume flow measurements are taken using time-resolved tomographic-PIV. Q at the glottal exit is extracted from PIV measurements and MFDR is computed from the waveform. Acoustic measurements (SPL)...