RT Journal Article
SR Electronic
T1 Overtone focusing in biphonic Tuvan throat singing
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 725267
DO 10.1101/725267
A1 Christopher Bergevin
A1 Chandan Narayan
A1 Joy Williams
A1 Natasha Mhatre
A1 Jennifer Steeves
A1 Brad Story
YR 2019
UL http://biorxiv.org/content/early/2019/08/05/725267.abstract
AB 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.