title: The Influence of Vowels on Vocal Fold Dynamics in the Tenor's Passaggio.
abstract: BACKGROUND
  The influence of vowels on the frequency region where registration events in male voices usually occur (passaggio) has not yet been clarified. Particularly, for tenors who frequently have to sing across the passaggio, it might be assumed that the vowel quality has an influence on the stability of phonation.
  
  
  METHODS
  In this investigation, six professionally trained Western classical tenors performed a glide from A3 (220 Hz) to A4 (440 Hz) and were recorded using high-speed videoendoscopy at 20,000 fps via transnasal flexible endoscopy. The participants produced transitions (1) from modal register to falsetto and (2) from modal register to stage voice above the passaggio on the vowels [aː], [iː], and [uː]. Simultaneously, acoustic and electroglottographic (EGG) signals were recorded. The glottal area waveform (GAW) open quotient (OQ), the EGG OQ, and the sample entropy derived from the EGG were calculated and phonovibrograms were established.
  
  
  RESULTS
  In comparison to [iː] and [uː], vowel [aː] showed lower values regarding the sample entropy and greater periodicity in the phonovibrograms during the passaggio. For [iː] and [uː], the falsetto showed greater GAW OQ than the stage voice above the passaggio but no great difference for vowel [aː]. There was a good agreement between GAW OQ and EGG OQ for GAW OQ values below .65. However, for values greater than .65, the EGG OQ showed greater disagreement.
  
  
  CONCLUSIONS
  The data support the hypothesis that the vowel condition influences the phonatory stability concerning the passaggio, suggesting that vowel [aː] is associated with greater phonation stability.
authors.affiliation: Institute of Musicians' Medicine, Freiburg University Medical Center and University of Freiburg, Faculty of Medicine, Freiburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Echternach
authors.affiliation: Institute of Musicians' Medicine, Freiburg University Medical Center and University of Freiburg, Faculty of Medicine, Freiburg, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Burk
authors.affiliation: Institute of Musicians' Medicine, Freiburg University Medical Center and University of Freiburg, Faculty of Medicine, Freiburg, Germany.
authors.forename: Marie
authors.initials: M
authors.lastname: Köberlein
authors.affiliation: University Medical Center Freiburg, Department of Radiology, Medical Physics, Freiburg, Germany into Dept. of Radiology, Medical Physics, Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Burdumy
authors.affiliation: Division of Phoniatrics and Pediatric Audiology at the Department of Otorhinolaryngology Head & Neck Surgery, Medical School, University Hospital Erlangen, Erlangen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Döllinger
authors.affiliation: Institute of Musicians' Medicine, Freiburg University Medical Center and University of Freiburg, Faculty of Medicine, Freiburg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Richter
mesh_terms: D006801:Humans; D008297:Male; D063346:Singing; D014827:Vocal Cords / Q000502:physiology*
keywords: High-speed videoendoscopy; Passaggio; Registers; Sample entropy; Tenors