Subharmonic/biphonic singing using vocal, ventricular, and aryepiglottic folds

Various singing styles using not only the true vocal folds but also the ventricular and aryepiglottic folds are found across diverse regions worldwide. This laryngeal activity induces a unique form of amplitude modulation through subharmonic vibration. This process generates either significant low-frequency components or a pressed phonation with broad spectral energy in the voice, enabling the production of sound pressures and a supra-normal voice quality that would be unachievable through conventional vocal fold oscillation alone. This presentation will provide an overview of past research, encompassing physiological observations and physical modeling, related to these unique ethnomusical singing styles found across different cultures. The mechanisms by which these additional laryngeal structures contribute to the unique acoustic properties will be presented. Furthermore, the discussion will address the current research challenges in this specialized field and outline promising future possibilities for both scientific inquiry and practical applications.