Overtone focusing in biphonic Tuvan throat singing
- York University, Canada
- Western University, Canada
- Walter Reed National Military Medical Center, United States
- University of Arizona, United States
Abstract
Khoomei is a unique singing style originating from the Central Asian republic of Tuva. Singers produce two pitches simultaneously: a booming low-frequency rumble alongside a hovering high-pitched whistle-like tone. The biomechanics of this biphonation are not well-understood. Here, we use sound analysis, dynamic magnetic resonance imaging, and vocal tract modeling to demonstrate how biphonation is achieved by modulating vocal tract morphology. Tuvan singers show remarkable control in shaping their vocal tract to narrowly focus the harmonics (or overtones) emanating from their vocal cords. The biphonic sound is a combination of the fundamental pitch and a focused filter state, which is at the higher pitch (1-2 kHz) and formed by merging two formants, thereby greatly enhancing sound-production in a very narrow frequency range. Most importantly, we demonstrate that this biphonation is a phenomenon arising from linear filtering rather than a nonlinear source.
Data availability
All data files (audio and imaging), as well as the relevant analysis software, are available via datadryad.org, https://doi.org/10.5061/dryad.cvdncjt14
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Overtone focusing in biphonic Tuvan throat singingDryad Digital Repository, https://doi.org/10.5061/dryad.cvdncjt14.
Article and author information
Author details
Christopher Bergevin
Funding
Natural Sciences and Engineering Research Council of Canada (RGPIN-430761-2013)
- Christopher Bergevin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Data were collected with approval of the York University Institutional Review Board (IRB protocol to Prof. Jennifer Steeves) This study was approved by the Human Participants Review Board of the Office of Research Ethics at York University (certificate #2017-132) and adhered to the tenets of the Declaration of Helsinki. All participants gave informed written consent and consent to publish prior to their inclusion in the study.
Copyright
© 2020, Bergevin et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Overtone focusing in biphonic Tuvan throat singing
eLife 9:e50476.
https://doi.org/10.7554/eLife.50476
Further reading
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