Kulning: Acoustic and Perceptual Characteristics of a Calling Style Used Within the Scandinavian Herding Tradition

Kulning, a loud, high-pitched vocal calling technique pertaining to the Scandinavian herding system, has attracted several researchers' attention, mainly focusing on cultural, phonatory and musical aspects. Less attention has been paid to the spectral and physiological properties that characterize Kulning tones, and also if there is a physiologically optimum pitch range. We analyzed tones produced by ten participants with varying experience in Kulning. They performed a phrase, pitch range G5 to C6 (784 to 1046 Hz), in three different conditions: starting (1) on pitch A5, (2) on the participant's preferred pitch, and (3) after the deepest possible inhalation, also on the participant's preferred pitch subglottal pressure (Psub) was measured as the oral pressure during /p/-occlusion. The quality of the Kulning was rated by a group of experts. The highest-rated tones all had a sound pressure level (SPL) at 0.3 m exceeding 115 dB and a pitch higher than 1010 Hz, while the SPL of the lowest rated tones was less than 108 dB at a pitch below 900 Hz. A multiple regression analysis was performed to evaluate the relationship between the ratings and Psub), SPL, level of the fundamental and the frequency at which a spectrum envelope dip occurred. Highly rated tones were started at maximum lung volumes, and on participants' preferred pitches. They all shared a high frequency of the spectrum envelope dip and a high level of the fundamental. In decreasing order of ratings, Condition 3 showed the highest values followed by Condition 2 and Condition 1. Each singer seemed to perform best within an individual Psub and pitch range. The relevance of the results to voice pedagogy, artistic, and compositional work is discussed.

Self-Perceived Voice Handicap During COVID19 Compulsory Facemask Use: A Comparative Study Between Portuguese and Spanish Speakers

This study investigates self-perceptions of voice-related handicap as a function of facemask use in the general working population during the COVID19 outbreak, using the Voice Handicap Index (VHI). Each VHI item was answered twice in a row; the first answer referred to the condition of not wearing a facemask (henceforth, the Without condition) and the second to the condition of using a facemask (henceforth, the With condition). VHI scores were collected via Google Forms (Google, Mountain View, California), targeting 2 groups of speakers of different nationalities, Portuguese (n = 261) and Spanish (n = 297). A Wilcoxon test was carried out to compare VHI scores between With and Without conditions for each group of speakers; a Mann-Whitney U test was used to compare groups within each condition. Results suggested that VHI overall scores and scores for all dimensions were higher for the With condition, for both Portuguese and Spanish speakers. When comparing groups of speakers, Spanish speakers presented higher scores for functional and emotional dimensions, for both With and Without conditions. In addition, the overall score for the Without condition was higher for Spanish speakers. No differences between groups were found for the total VHI score for the With condition. When comparing overall VHIdiff between speakers, that is, the difference in the VHI total score between With and Without conditions, no significant differences could be found. Thus, a multiple regression analysis was carried out between the VHIdiff and the independent variables of interest: age, sex, smoking habits, professional occupation, nationality, facemask type and its hours of use. The resulting model providing the highest association suggested that 2.5% of the variation in overall VHIdiff total score could be associated with sex, smoking habits, and professional level. Female smokers who use their voices during prolonged hours at work (e.g., teachers, lawyers, sales people) presented a higher VHI total score when wearing a mask. Future voice-related health interventions should address preventive strategies towards speaking behaviors leading to vocal fatigue and vocal effort as a consequence of compulsory facemask use, especially with respect to female professional voice users who smoke.

Menopausal Voice-Related Work Limitation Scale (MenoVWL): Development and Validation

OBJECTIVES

Menopause has been reported to affect the voice of female professional voice users (FPVUs). The present study aims at the development and validation of a scale to measure self-perceived menopausal voice-related limitation to work in FPVUs, henceforth the Menopausal Voice-Related Work Limitation Scale (MenoVWL).

METHODS

Items were drawn from previous studies on impacts of sex steroid hormones on voice, available validated scales, and in-depth interviews with post-menopausal FPVUs. A preliminary version with 16 items was evaluated by a panel of 15 voice experts. The resulting revised version was filled in online, together with questions on current endocrinological reproductive status and related symptoms, history of amenorrhea, professional occupation, and demographic information. Responses concerning only professional voice users were selected and inclusive and exclusive criteria were applied for correct allocation of participants into pre- and post-menopausal stages within a restrict age range;192 responses were subject to factorial analysis for MenoVWL validation. Cronbach's alpha measured internal reliability. The scale was tested by comparing MenoVWL scores between pre- and post-menopausal FPVUs (98 and 94, respectively).

RESULTS

Thirteen items were retained from the expert panel evaluation. Items presented a high Content Validity Index (.94 out of 1) and high Item Acceptance Ratio (86.25 %). Both exploratory and confirmatory factorial analysis rendered one dimension scale with an excellent internal consistency (Cronbach's alpha = .9). The results of a Mann-Whitney test showed a higher MenoVWL score for post- as compared to pre-menopausal FPVUs (Z = - 2.818; P = .005).

CONCLUSIONS

MenoVWL is a comprehensive and validated scale with a known factor structure. It constitutes a health care and safety outcome self-perceived measure of value to the early detection of voice-related limitations to work in FPVUs during menopause.

Long-Term Average Spectrum Characteristics of Portuguese Fado-Canção from Coimbra

Descriptions of acoustical characteristics of Fado, a Portuguese urban style sung in Lisbon and Oporto, are scarce, particularly concerning Fado-Canção, a related style sung in Coimbra. The present study aims at describing long-term average spectrum (LTAS) parameters of 16 professional singers while singing and reading the lyrics of a typical Fado-Canção. LTAS parameters were investigated in terms of: (1) equivalent sound level (L_eq); (2) spectral differences between 3 frequency bands 0-2, 2-5, and 5-8 kHz; and (3) quantification of spectral prominence between 2 and 4 kHz, calculated as the level difference between the peak in this frequency region and a reference trendline between 1 and 5 kHz, henceforth Formant Cluster Prominence (FCP). Given that Fado-Canção, besides Fado and traditional styles, originated also from classical singing, and that previous studies on Fado suggest the absence of a singer's formant cluster, the averaged LTAS for all Fado-Canção singers was further compared to the LTAS of two world-touring opera baritones singing an operatic aria and a lied. Results show that Fado-Canção is commonly sung with a L_eq of 86.4 dB and a FCP of about 10 dB, values significantly higher when compared to reading. The FCP in Fado-Canção_, although smaller than for the two classical opera singers' examples (14.8 and 20 dB, respectively), suggests that the style preserved some of its original lyrical influence. However, because younger singers present higher energy in the 5-8 kHz region relative to the remaining frequency bands as compared to older singers, it seems that Fado-Canção may be drifting towards non-classical vocal practices. FCP seems to be a promising straightforward method to quantify the degree of formant clustering around the region of the singer's formant in LTAS, allowing comparisons between different singers and singing styles.

Female Voice-Related Sexual Attractiveness to Males: Does it Vary With Different Degrees of Conception Likelihood?

Previous investigations have found that female voice-related attractiveness to males increases when both conception likelihood (CL) and voice fundamental frequency (f_o) are elevated. To test this hypothesis, we conducted a perceptual experiment where 78 heterosexual males rated sexual attractiveness of 9 female voice samples, recorded at menstrual, follicular and luteal phases of the menstrual cycle under two double-blinded randomly allocated conditions: a natural menstrual cycle (placebo condition) and when using an oral contraceptive pill (OCP condition). The voice samples yielded a total of 54 stimuli that were visually sorted and rated using Visor software. Concentrations of estrogens, progesterone and testosterone were analyzed, and measurements of speaking fundamental frequency (sf_o) and its standard deviation (sf_oSD), f_o derivative (df_o) and f_o slope were made. A multilevel ordinal logistic regression model nested in listeners and in females, and adjusted by phase and condition, was carried out to assess the association between ratings and: (1) phases and conditions; (2) sex steroid hormonal concentrations; and (3) voice parameters. A high probability of obtaining high ratings of voice sexual attractiveness was found for: (1) menstrual phase of placebo use and follicular phase of OCP use; (2) for low estradiol to progesterone ratio and testosterone concentrations; and (3) for low df_o. The latter showed a moderate statistical association with ratings of high attractiveness, as compared with the small association found for the remaining variables. It seems that the voice is a weak cue for female CL. Female sexual attraction to males may be a consequence of what females do in order to regulate their extended sexuality across the menstrual cycle rather than of estrus cues, the use of paralinguistic speech patterns being an example.

Glottal Airflow and Glottal Area Waveform Characteristics of Flow Phonation in Untrained Vocally Healthy Adults

OBJECTIVE

To examine flow phonation characteristics with regard to vocal fold vibration and voice source properties in vocally healthy adults using multimodality voice measurements across various phonation types (breathy, neutral, flow, and pressed) and loudness conditions (typical, loud, and soft).

PARTICIPANTS AND METHODS

Vocal fold vibration, airflow, acoustic, and subglottal pressure was analyzed in 13 untrained voices (six female and seven male). Participants repeated the syllable / pæ:/ using breathy, neutral, flow, and pressed phonation during typical, loud, and soft loudness conditions. Glottal area (GA) waveforms were extracted from high-speed videoendoscopy; glottal flow was derived from inverse filtering the airflow or the audio signal; and subglottal pressure was measured as the intraoral pressure during /p/ occlusion.

RESULTS

Changes in phonation type and loudness conditions resulted in systematic variations across the relative peak closing velocity derived from the GA waveform for both males and females. Amplitude quotient derived from the flow glottogram varied across phonation types for males.

CONCLUSION

Multimodality evaluation using the GA waveform and the inverse filtered waveforms revealed a complex pattern that varied as a function of phonation types and loudness conditions across males and females. Emerging findings from this study suggests that future large-scale studies should focus on spatial and temporal features of closing speed and closing duration for differentiating flow phonation from other phonation types in untrained adults with and without voice disorders.

Fundamental Frequency Variations Across the Menstrual Cycle and the Use of an Oral Contraceptive Pill

Purpose Concentrations of sex steroid hormones-estrogens, progesterone, and testosterone-have been associated with premenstrual and menstrual vocal symptoms. However, the extent to which these symptoms may be reflected on acoustical features of the voice is still debated. This study investigates variations in fundamental frequency (f _o) and related parameters in connected speech across phases of the menstrual cycle and during the use of a combined oral contraceptive pill (OCP). Method Electrolaryngographic recordings were made, and blood samples were collected at three different phases of the menstrual cycle-menstrual, follicular, and luteal-for placebo and OCP use. These two conditions were blindly and randomly allocated in the study. Speaking f _o (SFF), SFF standard deviation, SFF rate of change, SFF slope, maximum and minimum f _o, and f _o range were extracted for nine healthy females while reading a phrase from the Rainbow Passage. Concentrations of sex hormones were analyzed in serum. Nonparametric statistical tests were carried out to assess differences between phases and conditions. Results SFF, its standard deviation, and maximum f _o were significantly different between phases of the menstrual cycle for placebo use only. Menstrual phase showed the lowest values. Maximum and minimum f _o were significantly different between placebo and OCP use for menstrual and follicular phases, respectively. Conclusions Fluctuations in sex steroid hormones across the menstrual cycle alter f _o in speech more than a particular hormonal concentration. OCP use seems to have a stabilizing effect on the voice relative to f _o and related parameters in speech.

Spectrum Effects of a Velopharyngeal Opening in Singing

The question whether or not a velopharyngeal opening is advantageous in singing has been discussed for a very long time among teachers of singing. The present investigation analyzes the acoustic consequences of a large, a narrow, and a nonexistent velopharyngeal opening (VPO). A divided flow mask (nasal and oral) connected to flow transducers recorded the nasal and oral DC flows in four female and four male classically trained singers while they sang vowel sequences at different pitches under these three experimental conditions. Acoustic effects were analyzed in three long-term average spectra parameters: (i) the sound level at the fundamental frequency, (ii) the level of the highest peak below 1 kHz, and (iii) the level of the highest peak in the 2-4 kHz region. For a narrow VPO, an increase in the level of the highest peak in the 2-4 kHz region was observed. As this peak is an essential voice component in the classical singing tradition, a narrow VPO seems beneficial in this type of singing.

Voice Source Variation Between Vowels in Male Opera Singers

OBJECTIVES

The theory of nonlinear 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. In addition, 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 maximum flow declination rate (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 source-filter interaction, but the variation does not seem to be dependent on the frequency distance between F1 and its closest partial.

Contact quotient versus closed quotient: a comparative study on professional male singers

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), whereas 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- and EGG-based measures collected from five professional male singers were compared, under different pitch and loudness conditions.

RESULTS

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 (ie, 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- and EGG-based closed quotients differ and must not be confused.

Intonation and expressivity: a single case study of classical western singing

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.

Effects of the menstrual cycle and oral contraception on singers' pitch control

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.

The effects of a third generation combined oral contraceptive pill on the classical singing voice

The success of professional operatic singers depends upon the quality of their vocal mechanism. This is known to be sensitive to changes in the endocrine environment. Despite a widespread belief among singers that vocal quality changes according to the stage of the menstrual cycle, this has received little attention. In particular, the possibility that use of the contraceptive pill might stabilize vocal quality by "dampening" hormonal fluctuations has not previously been studied systematically. Here, we show that drospirenone containing oral contraceptive pill (Yasmin, Schering AG, West Sussex, UK) with antiandrogenic and antimineralocorticoid properties demonstrates a significant reduction in the irregularity of the pattern of vibration of the vocal folds during the performance of highly trained classical singers. This study constitutes the first double blind, randomized placebo controlled trial to assess the effects of the contraceptive pill on the patterns of vibration of the vocal folds during the performance of Western classical singing repertoire.