title: Just noticeable differences of open quotient and asymmetry coefficient in singing voice.
abstract: This study aims to explore the perceptual relevance of the variations of glottal flow parameters and to what extent a small variation can be detected. Just Noticeable Differences (JNDs) have been measured for three values of open quotient (0.4, 0.6, and 0.8) and two values of asymmetry coefficient (2/3 and 0.8), and the effect of changes of vowel, pitch, vibrato, and amplitude parameters has been tested. Two main groups of subjects have been analyzed: a group of 20 untrained subjects and a group of 10 trained subjects. The results show that the JND for open quotient is highly dependent on the target value: an increase of the JND is noticed when the open quotient target value is increased. The relative JND is constant: deltaOq/Oq = 14% for the untrained and 10% for the trained. In the same way, the JND for asymmetry coefficient is also slightly dependent on the target value--an increase of the asymmetry coefficient value leads to a decrease of the JND. The results show that there is no effect from the selected vowel or frequency (two values have been tested), but that the addition of a vibrato has a small effect on the JND of open quotient. The choice of an amplitude parameter also has a great effect on the JND of open quotient.
authors.affiliation: LAM (UPMC, CNRS, Ministère de la culture), Paris, France. nathalie.henrich@lam.jussieu.fr
authors.forename: Nathalie
authors.initials: N
authors.lastname: Henrich
authors.forename: Gunilla
authors.initials: G
authors.lastname: Sundin
authors.forename: Daniel
authors.initials: D
authors.lastname: Ambroise
authors.forename: Christophe
authors.initials: C
authors.lastname: d'Alessandro
authors.forename: Michèle
authors.initials: M
authors.lastname: Castellengo
authors.forename: Boris
authors.initials: B
authors.lastname: Doval
mesh_terms: D000328:Adult; D004056:Differential Threshold / Q000502:physiology; D005260:Female; D005931:Glottis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009146:Music; D010699:Phonation / Q000502:physiology*; D010700:Phonetics; D014833:Voice Quality