Jianwu Dang, Kiyoshi Honda
A new method for measuring vocal tract
transmission characteristics
Abstract:A new method is proposed for the purpose of direct measurement of vocal tract transmission. characteristics. This method evaluates the vocal tract transfer function from an arbitrary location in the vocal tract to its radiation end by measuring volume velocities at the two locations. An experimental study was conducted on acoustic tubes of various known shapes in order to evaluate the accuracy of the method. Two types of excitation sound sources, a sweeptone signal and the natural glottal sound source, were used for the experiment. Resonance and antiresonance frequencies obtained from the acoustic tubes were consistent with theoretical values within 4%. Compared with previous methods (Van den berg, 1955; Fujimura, et al, 1971; Lindqvist-Gauffin, et al, 1976), the present method has two major advantages: first, the characteristics and positions of the excitation sound source have less influence on the measurement of the frequencies of both the peaks and zeros; second, the measured results exactly represent acoustic properties of the measurement portion from the measurement location to the radiation end. By taking these advantages, the glottal sound can serve as the excitation sound source for the direct measurement. The spectrum details of the vocal tract transmission characteristics can be examined by changing the measurement location.