Persona:
Filipa M.B., Lã

Cargando...
Foto de perfil
Dirección de correo electrónico
ORCID
0000-0001-5560-7406
Fecha de nacimiento
Proyectos de investigación
Unidades organizativas
Puesto de trabajo
Apellidos
Filipa M.B., Lã
Nombre de pila
Nombre

Resultados de la búsqueda

Mostrando 1 - 8 de 8
  • Publicación
    Formant Tuning Strategies in Professional Male Opera Singers
    (Elsevier, 2013-05) Sundberg, Johan; Filipa M.B., Lã; Gill, Brian P.; Filipa M.B., Lã
    The term “formant tuning” is generally used for the case that one of the lowest formant frequencies coincides with the frequency of a source spectrum partial. Some authors claim that such coincidence is favorable and belongs to the goals of classical opera voice training, whereas other authors have found evidence for advising against it. This investigation analyzes the relationships between formant frequencies and partials in professional singers, who sang scales on the vowels /a/, /u/, /i/, and /ae/ in a pitch range including the passaggio, that is, the fundamental frequency range of approximately 300–400 Hz, applying either of the two singing strategies that are typically used (1) in classical and (2) in nonclassical singing, respectively. Formant frequencies of each note in the scales were measured by inverse-filtering the acoustic signal. In the classical style, the first formant tended to be lower than in the nonclassical style. Neither the first nor the second formant tended to change systematically between scale tones, such that on some scale tones either or both formants was just below, just above, or right on a spectrum partial. In many cases, singers produced similar spectrum characteristics of the top tones of the scales with different first and second formant frequencies. Regardless of whether the first formant was slightly lower, slightly higher, or right on a partial, the properties of the voice source did not seem to be affected.
  • Publicación
    Voice source variation between vowels in male opera singers
    (Elsevier, 2016-09-01) Sundberg, Johan; Filipa M.B., Lã; Gill, Brian P.; Filipa M.B., Lã
    Objectives: The theory of non-linear source-filter interaction predicts that the glottal voice source should be affected by the frequency relationship between formants and partials. An attempt to experimentally verify this theory is presented. Study design: Glottal voice source and electrolaryngograph (ELG) signal differences between vowels were analyzed in vowel sequences, sung at four pitches with the same degree of vocal loudness by professional opera singers. Also, the relationships between such differences and the frequency distance between the first formant (F1) and its closest partial were examined. Methods: A digital Laryngograph microprocessor was used to simultaneously record audio and ELG signals. The former was inverse-filtered and voice source parameters and formant frequencies were extracted. The amplitude quotient of the derivative of the ELG signal (AQdELG) and the contact quotient were also compared. Results: A one-way repeated measures ANOVA revealed significant differences between vowels, for contact quotient at four pitches and for MFDR at three pitches. For other voice source parameters, differences were found at one or two pitches only. No consistent correlation was found between MFDR and the distance between F1 and its closest partial. Conclusions: The glottal voice source tends to vary between vowels, presumably because of non-linear source-filter interaction, but the variation does not seem to be dependent upon the frequency distance between F1 and its closest partial
  • Publicación
    Contact quotient versus closed quotient: a comparative study on professional male singers
    (Elsevier, 2015-03) Filipa M.B., Lã; Sundberg, Johan; Filipa M.B., Lã
    Objectives: The term “closed quotient” is frequently used for data derived both from inverse filtering and from electroglottography. In the former case it is defined as the ratio between the closed phase and the period, as measured in flow glottograms (FLOGG), while in the latter case it is defined as the time interval between the falling and rising parts of the electroglottogram (EGG), measured at some percentage of the peak-to-peak amplitude. The study aims at analyzing differences between EGG and FLOGG based closed quotients and their relationships with voice source parameters. Study Design: Comparative study Methods: FLOGG based and EGG based measures collected from five professional male singers were compared, under different pitch and loudness conditions. Results: As compared with the FLOGG based quotient, the EGG based quotient (i) varied more between subjects, (ii) presented greater values, (iii) varied less with subglottal pressure, (iv) varied less with the normalized amplitude quotient (i.e. the ratio between the flow pulse amplitude and the product of period and maximum flow declination rate), and (v) varied less with the relative amplitude of the voice source fundamental. Conclusions: Although positively related, FLOGG based and EGG based closed quotients differ and must not be confused.
  • Publicación
    Intonation and Expressivity: A Single Case Study of Classical Western Singing
    (Elsevier, 2013-05) Sundberg, Johan; Himonides, Evangelos; Filipa M.B., Lã
    Previous studies have shown that singers tend to sharpen phrase-peak tones as compared with equally tempered tuning (ETT). Here we test the hypothesis that this can serve the purpose of musical expressivity. Data were drawn from earlier recordings, where a professional baritone sang excerpts as void of musical expression as he could (Neutral) and as expressive as in a concert (Concert). Fundamental frequency averaged over tones was examined and compared with ETT. Phrase-peak tones were sharper in excited examples, particularly in the Concert versions. These tones were flattened to ETT using the Melodyne software. The manipulated and original versions were presented pairwise to a musician panel that was asked to choose the more expressive version. By and large, the original versions were perceived as more expressive, thus supporting the common claim that intonation is a means for adding expressivity to a performance.
  • Publicación
    Professional male singers’ formant strategies for the vowel /a/
    (Taylor & Francis, 2011-11-15) Sundberg, Johan; Filipa M.B., Lã; Gill, Brian P.; Filipa M.B., Lã
    Certain spectrum characteristics have been identified as important for register equalization around the male passaggio, an effect ascribed to formant tuning although descriptions of formant tuning diverge. Eight professional singers sang scales including their passaggio range on different vowels, applying two formant tuning strategies as found in (Citation) classical and (Citation) non-classical singing. Formant frequencies were measured using inverse filtering. Results revealed differences between the two strategies. For the classical formant tuning, systematic changes of formant frequencies with pitch were observed. For the highest note sung on /a/, was below the second partial and in the vicinity of the third. Similar spectrum characteristics were achieved by different and values between singers.
  • Publicación
    Effects of the menstrual cycle and the oral contraception on singer´s pitch control
    (American Speech-Language-Hearing Association (ASHA), 2012-02-01) Filipa M.B., Lã; Sundberg, Johan; Howard, David M.; Sa Couto, Pedro; Freitas, Adelaide; Filipa M.B., Lã
    Purpose: Difficulties with intonation and vibrato control during the menstrual cycle have been reported by singers; however, this phenomenon has not yet been systematically investigated. Method: A double-blind randomized placebo-controlled trial assessing effects of the menstrual cycle and use of a combined oral contraceptive pill (OCP) on pitch control in singing is presented. Audio-electrolaryngograph recordings were made and blood samples were taken from 9 singers in each of the 3 phases of the menstrual cycle both under the placebo and the OCP conditions for a total of 6 months. Participants sang an exercise consisting of an ascending octave followed by a descending major triad, starting on pitches F4 and B4. Pitch control was assessed in terms of the octave's deviations from pure intonation and of the vibrato rate and extent. Results: Significant differences were found between the 3 phases of the cycle regarding octave size only for pitch F5 during OCP use. Significant vibrato rate differences between placebo and OCP conditions were found only for pitch F5. Conclusion: OCP use may have an effect on pitch control in singers. Possible explanations point to a complex interaction between hormonal milieu and pitch control, enhancing the need for longitudinal studies.
  • Publicación
    Pregnancy and the Singing Voice: Reports from a Case Study
    (Elsevier, 2012-07) Sundberg, Johan; Filipa M.B., Lã
  • Publicación
    Soul and Musical Theatre. A comparison of two vocal styles
    (Elsevier, 2017-03-01) Hallqvist, Hanna; Filipa M.B., Lã; Sundberg, Johan; Filipa M.B., Lã
    The phonatory and resonatory characteristics of nonclassical styles of singing have been rarely analyzed in voice research. Six professional singers volunteered to sing excerpts from two songs pertaining to the musical theater and to the soul styles of singing. Voice source parameters and formant frequencies were analyzed by inverse filtering tones, sung at the same fundamental frequencies in both excerpts. As compared with musical theater, the soul style was characterized by significantly higher subglottal pressure and maximum flow declination rate. Yet sound pressure level was lower, suggesting higher glottal resistance. The differences would be the effects of firmer glottal adduction and a greater frequency separation between the first formant and its closest spectrum partial in soul than in musical theater.