Front cover image for A Study of Vibrato in Relation to Fundamental Frequency - Formant Interactions

A Study of Vibrato in Relation to Fundamental Frequency - Formant Interactions

The linear source-filter theory states that the source (vocal signal) is independent of the filter (vocal tract). Recent research explores non-linear source-filter interaction that occurs when the f0 is just above F1, resulting in destabilization of the vocal signal reflected by pitch breaks and subharmonics. Vibrato, a vocal ornament, is the periodic fluctation of pitch and intensity, measured by rate, extent, and regularity. The objective of this study was to examine if the addition of vibrato would reduce the number of instabilities occuring due to f0 - F1 interaction. Professional singers performed vocal exercises that set up scenarios where f0 was in close proximity (under, on, above) to F1 using both straight tone and vibrato. Results were examined via subjective ratings and acoustical analyses for pitch breaks, subharmonics, and vibrato characteristics. It was determined that the addition of vibrato significantly reduced the number of instabilities in the vocal signal
Thesis, Dissertation, English, 2012
University of Memphis