Airflow Vibrato in Emotional Singing: A Pilot Study
Channel: Sri Nandamudi
Date: 13/05/2020

Objectives: To compare objective acoustic and airflow (AF) measures across five different emotions – happiness, sadness, anger, tenderness, and neutral, sung by a Western classical singer. Such information is important to both basic phonatory science and to the pedagogy of expressive singing.
Method: The performer is an active Western classical soprano and university singing teacher with over 15 years of professional performance experience. The subject sang “The Star-Spangled Banner” using the five different emotions mentioned above. Praat, the Glottal Enterprises aerodynamic system (MSIF-2), and custom software were used. Eight words were analyzed: “oh”, “say”, “see”, “by”, “light”, “proudly”, “hailed”, and “gleaming”. The dependent variables were rate, extent, and variability of fo and AF vibrato, average AF, average fo, average intensity (dB), and the phase difference between fo and AF vibrato. 
Results: The duration of the song for the emotions “sadness” and “tenderness” (ave. 29.76 sec) was longer compared to the other three (ave. 23.71 sec). “Anger” was produced with a higher average AF (M=293.6 cc/s, SD=39.8 cc/s) compared to other emotions, e.g., “gleaming” had an average of 109.8 cc/s. “Anger” also typically exhibited higher vibrato extents and variability (SD), and faster vibrato rates; this was followed by “happiness” and “neutral”. Figure 1 compares the means and standard deviations of all eleven variables for the word “Light”. “Sadness” and “Tenderness” primarily displayed lower AF values and less variability in vibrato rates and extents.
Conclusion: The greatest contrast was between “anger’ and “tenderness”, with higher average AF, fo and AF vibrato extents and rates, and greater variability (SDs). The decreased variability for “tenderness” suggests a more consistent production of vibrato. More singers need to participate in such a study as this in order to understand the variability of objective measures across emotional expressions. 

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Figure 1: Relative measures of all eleven variables for the word “Light” (similar figures will be shown and discussed for the other words, as well).

Rosalie Gagnon, B.S. Student, Department of Communication Sciences and Disorders, Grand Valley State University, Grand Rapids, MI 49503
Sri Nandamudi, Ph.D., CCC-SLP, Assistant Professor in SLP, Department of Communication Sciences and Disorders, Grand Valley State University, Grand Rapids, MI 49503
Ronald Scherer, Ph.D., Distinguished Research Professor, Department of Communication Sciences and Disorders, Bowling Green State University, Bowling Green, OH 43403