Automatic Measurement of Sounds Produced by a Whistling Vocal Tract Model−Measurement of the Fundamental Frequency of the Generated Sounds and the Flow Range

ABSTRACT Previous studies have aimed to elucidate the principles of whistling by constructing vocal tract models using computed tomography data of the vocal tract during whistling. In addition, studies have been conducted on whistling pitch change models, in which the plates of the vocal tract model are adjusted to simulate changes in the vocal tract shape due to pitch changes. However, these studies often required manual operation of measuring devices and the interpretation of gauges. In this study, we developed a device that automates the measurement of sounds emitted by a vocal tract model during whistling. Using this device, we estimated the duration during which a stable whistling sound was generated and examined a method to measure the fundamental frequency and flow rate when the sound quality was optimal. Consequently, the device can automatically adjust, measure the flow rate, and analyze the generated sound. Furthermore, by using the distortion rate, we could estimate the period during which a whistling sound was generated and determine the fundamental frequency at which the sound quality was optimal.