- 著者
- Fumiaki Taguchi Sadao Hiroya Yasufumi Uezu Takemi Mochida
- 出版者
- ACOUSTICAL SOCIETY OF JAPAN
- 雑誌
- Acoustical Science and Technology (ISSN:13463969)
- 巻号頁・発行日
- vol.41, no.5, pp.800-803, 2020-09-01 (Released:2020-09-01)
- 参考文献数
- 19
- 被引用文献数
- 1
- 著者
- Yasufumi Uezu Sadao Hiroya Takemi Mochida
- 出版者
- ACOUSTICAL SOCIETY OF JAPAN
- 雑誌
- Acoustical Science and Technology (ISSN:13463969)
- 巻号頁・発行日
- vol.41, no.5, pp.720-728, 2020-09-01 (Released:2020-09-01)
- 参考文献数
- 30
- 被引用文献数
- 2
Auditory feedback has a crucial role in stably controlling speaking and singing. Formant-transformed auditory feedback (TAF) is used to investigate the relationship between perturbation to the formant frequency and the compensatory response to clarify the mechanism of auditory-speech motor control. Although previous studies for formant TAF applied linear predictive coding (LPC) to estimate formant frequencies, LPC estimates false formants for high-pitch voice. In this paper, we investigate how different vocal-tract spectrum estimation methods in real-time formant TAFs affect the compensatory response of formant frequencies to perturbations. A phase equalization-based autoregressive exogenous model (PEAR) is applied to the TAF system as a formant estimation method that can estimate the formant frequency more accurately and robustly than LPC can. Fifteen Japanese native speakers were asked to repeat the Japanese syllables /he/ or /hi/ while receiving feedback sounds whose formants F1 and F2 were transformed. From the results for the /he/ condition, the F1 compensatory response for PEAR was significantly larger than that of LPC, and the compensation error in the F1–F2 plane for PEAR was less than that for LPC. Our results suggest that PEAR can increase both the accuracy of formant frequency estimation and the naturalness of the transformed speech sound.
- 著者
- Yasufumi Uezu Tokihiko Kaburagi
- 出版者
- ACOUSTICAL SOCIETY OF JAPAN
- 雑誌
- Acoustical Science and Technology (ISSN:13463969)
- 巻号頁・発行日
- vol.37, no.6, pp.267-276, 2016-11-01 (Released:2016-11-01)
- 参考文献数
- 17
- 被引用文献数
- 1 4
When one of the dominant harmonics (the fundamental frequency and its harmonic components) is close to the first formant frequency, the effect of the source-filter interaction can induce voice register transition, in which the vocal-fold vibration becomes unstable and the pitch jumps abruptly. We investigated the relationship between the dominant harmonics, the first formant frequency, and the pitch jump width in the modal-falsetto transition to examine the effect of source-filter interaction. We measured temporal patterns of the fundamental frequency and the first formant when subjects performed rising glissandi with /a/ and /i/ vowels. For the /a/ vowel, there were weak proximity relationships between the dominant harmonics and first formant during the transition, indicating that source-induced transition occurred. For the /i/ vowel, in contrast, the fundamental frequency was regularly close to the first formant in the transition, indicating that the acoustically induced transition was caused by the source-filter interaction. Additionally, it was found that the difference between these two mechanisms had little influence on the pitch jump width. Finally, we concluded that the source-filter interaction is a contributory factor of the modal-falsetto transition, in agreement with foregoing studies.