Fundamental Frequency Variation Research Articles

INTERHARMONICS UNDER FUNDAMENTAL FREQUENCY VARIATIONS

As the power system is going through a transition to become more sustainable, new technologies are introduced resulting in new types of power quality disturbances. This paper illustrates examples of different interharmonic patterns observed in selected sustainable energy sources and loads. An investigation is made into the signal processing aspects of interharmonics of non-stationary signals with focus on fundamental frequency variations. This paper also discusses associated challenges, e.g., if they are real interharmonics or a signal processing error misinterpreted as interharmonics. Case studies illustrated are on a wind farm, a measurement set-up with a PV inverter and single-phase AC EV charger, and a microgrid. The methods used are STFT, desynchronized processing technique and sliding-window ESPRIT. Identifying the sources of the observed interharmonics are not within the scope of this work.

Voice modulatory cues to structure across languages and species.

Voice modulatory cues such as variations in fundamental frequency, duration and pauses are key factors for structuring vocal signals in human speech and vocal communication in other tetrapods. Voice modulation physiology is highly similar in humans and other tetrapods due to shared ancestry and shared functional pressures for efficient communication. This has led to similarly structured vocalizations across humans and other tetrapods. Nonetheless, in their details, structural characteristics may vary across species and languages. Because data concerning voice modulation in non-human tetrapod vocal production and especially perception are relatively scarce compared to human vocal production and perception, this review focuses on voice modulatory cues used for speech segmentation across human languages, highlighting comparative data where available. Cues that are used similarly across many languages may help indicate which cues may result from physiological or basic cognitive constraints, and which cues may be employed more flexibly and are shaped by cultural evolution. This suggests promising candidates for future investigation of cues to structure in non-human tetrapod vocalizations.This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part I)’.

Effects of dynamic pitch manipulation methods on speech perception in noise by older listeners with hearing loss

Dynamic pitch, as defined by the variation in fundamental frequency (f0) of speech, is a major acoustic cue in speech perception. While dynamic pitch manipulation negatively affects speech perception in noise on a group level, there is substantial variability across older listeners with hearing loss. The manipulation method used in previous studies, however, may distort pitch contours in natural speech. In this study, a new manipulation method is employed by exaggerating pitch contours above mean pitch. The primary purpose of the study is to compare the effects of these two manipulation methods on speech recognition in noise by older listeners with hearing loss. The secondary purpose is to examine the connection between individuals’ responses to dynamic pitch manipulation and intonation perception. Speech reception threshold in noise was measured from 8 older listeners (mean age 74.5 years) with mild-moderate sensorineural hearing loss. Intonation perception was measured by a 2-alternative discrimination paradigm. Data up to date suggest a stronger effect from the new method, with the weakened dynamic pitch being more beneficial than the original pitch contour. Further, individuals’ intonation perception is associated with their response to pitch manipulation. The theoretical and clinical implications will be discussed. [Word supported by NIH.]

How intonation and articulation cues impact gender perception for cisgender and transgender speakers

Gender identities beyond cisgender male and female are poorly represented in speaker gender perception research. Incorporating transgender speakers may reveal speech characteristics that extend beyond hetero-cis-normative standards and better reflect listeners' real-world experiences and cognitive representations of gender. This study compared how intonation and articulation impact listeners’ judgements of speaker gender identity and masculinity/femininity using cisgender male and female, transfeminine, and transmasculine speakers. Cisgender speakers' fundamental and formant frequencies were shifted to gender-ambiguous range and transfeminine and transmasculine speakers to prototypically cisgender female or male range, respectively. Listeners judged speaker gender in conditions that either removed fundamental frequency variation, frequencies above 500 Hz, or both cues. There were nonuniform effects of intonation and articulatory modifications on listener perceptions of gender across speaker groups. However, articulation influenced listener perception more than intonation. When listeners heard articulatory as compared to intonation cues, gender identification scores were generally higher for all speaker groups and masculinity/femininity scores more aligned with cisgender female and transfeminine speakers’ gender identities. Although most prior work with transgender speakers has focused on intonation, articulation can substantially impact gender perception and should be considered in gender affirming communication training.

Low-Profile Harmonic Transponder for IoT Applications

This paper proposes a novel single-layer, low-profile harmonic transponder to be integrated with the printable diodes based on Si particles. The introduced prototype consists of two bowtie dipoles that are directly matched to the harmonic generation element at a fundamental 2.45GHz frequency and also at the corresponding second harmonic 4.9GHz frequency. Therefore, the antennas and T-matching parts can be manufactured as separate inlays using a single layer-substrate. Besides the new prototype, the harmonic conversion loss (CL) is theoretically and experimentally investigated. In this regard, the equivalent circuit is driven and utilized to analyze the CL performance with variations in fundamental frequency and input power. The introduced transponder outperforms the state-of-the-art work from the printability, size, and CL point of views.

The Relationships Among Vocal Variability, Vocal-Articulatory Coordination, and Dysphonia in Children

ObjectiveThe purpose of this study was to evaluate the relationship between vocal variability and variability of vocal-articulatory coordination in children. Furthermore, this study examined if this relationship was impacted by pediatric dysphonia. Study DesignRetrospective analysis of speech samples in the Arizona Child Acoustic Database. MethodsSpeech samples from children 2–7 years of age were selected for analysis. Vocal variability was defined as the coefficient of variation (CoV) of fundamental frequency, taken from the center of sustained vowels. Variability of vocal-articulatory coordination was defined as the CoV of voice onset time (VOT) of voiceless stop consonants. Both objective and subjective measures of dysphonia were completed for each participant. ResultsChildren had a negative correlation between VOT variability and vocal variability. Further analysis indicated that this relationship was present in children with typical developmental levels of dysphonia but absent for children with moderate to severe dysphonia. Increased dysphonia severity was associated with increased vocal variability. ConclusionIncreased VOT variability was associated with decreased vocal variability in children with dysphonia severities consistent with typical vocal development. However, this relationship was not present in children with moderate to severe dysphonia. This study suggests that future work is needed to examine the relationships between the vocal system and vocal-articulatory coordination in children with and without diagnosed voice disorders.

A Cross-sectional Study of Perceptual and Acoustic Voice Characteristics in Healthy Aging

The human voice qualitatively changes across the lifespan. Although some of these vocal changes may be pathologic, other changes likely reflect natural physiological aging. Normative data for voice characteristics in healthy aging is limited and disparate studies have used a range of different acoustic features, some of which are implicated in pathologic voice changes. We examined the perceptual and acoustic features that predict healthy aging. Participants (N = 150) aged between 50 and 92 years performed a sustained vowel task. Acoustic features were measured using the Multi-Dimensional Voice Program and the Analysis of Dysphonia in Speech and Voice. We used forward and backward variable elimination techniques based on the Bayesian information criterion and linear regression to assess which of these acoustic features predict age and perceptual features. Hearing thresholds were determined using pure-tone audiometry tests at frequencies 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz. We further explored potential relationships between these acoustic features and clinical assessments of voice quality using the Consensus Auditory-Perceptual Evaluation of Voice. Chronological age was significantly predicted by greater voice turbulence, variability of cepstral fundamental frequency, low relative to high spectral energy, and cepstral intensity. When controlling for hearing loss, age was significantly predicted by amplitude perturbations and cepstral intensity. Clinical assessments of voice indicated perceptual characteristics of speech were predicted by different acoustic features. For example, breathiness was predicted by the soft phonation index, mean cepstral peak prominence, mean low-high spectral ratio, and mean cepstral intensity. Findings suggest that acoustic features that predict healthy aging are different than those previously reported for the pathologic voice. We propose a model of healthy and pathologic voice development in which voice characteristics are mediated by the inability to monitor vocal productions associated with age-related hearing loss. This normative data of healthy vocal aging may assist in separating voice pathologies from healthy aging.

Effects of speaking style on the shape of fundamental frequency distributions

The present study has two main goals. The first is to describe the effects of three speaking styles (spontaneous interview, sentence reading and word list reading) on statistical estimators of fundamental frequency (f0) variability (mean, standard deviation, skewness and kurtosis) in five female and five male speakers of Brazilian Portuguese (BP). Most f0 contours of word reading are bimodal. Analysis of their time-normalized contours suggests this is caused by the time-compressed realization of fast transitions from low to high or high to low tones aligned with stressed syllables. Considering only unimodal distributions, results show that there are no statistically significant effects in the male data for any of the four variability estimators. Effects show up in female data. Spontaneous style has statistically significant higher mean, SD and skewness than read speech. Findings in the previous literature indicate the reverse pattern, though, for languages other than BP. The second goal of the study is to characterize the statistical properties of f0 distributions beyond mean and SD. Results confirm previous observations that most f0 distributions have positive skewness, are left-tailed and have kurtosis values that deviate significantly from the normal because of large deviations from the central or modal value. A distribution fitting procedure tested six distributions. The asymmetric Burr type XII distribution emerges as the one that best fits the data in the corpus. Results show that two of the parameters that determine its shape correlate well with the empirical f0 distribution values of SD and skewness. Important effects of speaking style on f0 seen in female speakers can be reproduced by combinations of the Burr distributions’ parameters.

The voice of COVID-19: Acoustic correlates of infection in sustained vowels.

COVID-19 is a global health crisis that has been affecting our daily lives throughout the past year. The symptomatology of COVID-19 is heterogeneous with a severity continuum. Many symptoms are related to pathological changes in the vocal system, leading to the assumption that COVID-19 may also affect voice production. For the first time, the present study investigates voice acoustic correlates of a COVID-19 infection based on a comprehensive acoustic parameter set. We compare 88 acoustic features extracted from recordings of the vowels /i:/, /e:/, /u:/, /o:/, and /a:/ produced by 11 symptomatic COVID-19 positive and 11 COVID-19 negative German-speaking participants. We employ the Mann-Whitney U test and calculate effect sizes to identify features with prominent group differences. The mean voiced segment length and the number of voiced segments per second yield the most important differences across all vowels indicating discontinuities in the pulmonic airstream during phonation in COVID-19 positive participants. Group differences in front vowels are additionally reflected in fundamental frequency variation and the harmonics-to-noise ratio, group differences in back vowels in statistics of the Mel-frequency cepstral coefficients and the spectral slope. Our findings represent an important proof-of-concept contribution for a potential voice-based identification of individuals infected with COVID-19.

Acoustic Measures of Brazilian Transgender Women's Voices: A Case-Control Study.

Objective: This study aims to compare the acoustic vocal analysis results of a group of transgender women relative to those of cisgender women.Methods: Thirty transgender women between the ages of 19 and 52 years old participated in the study. The control group was composed of 31 cisgender women between the ages of 20 and 48 years old. A standardized questionnaire was administered to collect general patient data to better characterize the participants. The vowel /a/ sounds of all participants were collected and analyzed by the Multi-Dimensional Voice Program advanced system.Results: Statistically significant differences between cisgender and transgender women were found on 14 measures: fundamental frequency, maximum fundamental frequency, minimum fundamental frequency, standard deviation of fundamental frequency, absolute jitter, percentage or relative jitter, fundamental frequency relative average perturbation, fundamental frequency perturbation quotient, smoothed fundamental frequency perturbation quotient, fundamental frequency variation, absolute shimmer, relative shimmer, voice turbulence index (lower values in the cases), and soft phonation index (higher values in the cases). The mean fundamental frequency value was 159.046 Hz for the cases and 192.435 Hz for the controls.Conclusion: Through glottal adaptations, the group of transgender women managed to feminize their voices, presenting voices that were less aperiodic and softer than those of cisgender women.

Structural change detection applying long-term seismic interferometry by deconvolution method to a modern civil engineering structure (New Zealand)

Pulse-wave propagation velocity and resonance frequency measured in civil engineering structures are both related to structural design. Monitoring their variation following seismic strong shaking provides information about the immediate building capacity. Joint-interpretation of frequency and velocity variation requires a better understanding of the processes controlling seismic structural health. In this study, we analysed 8 years of earthquake data recorded by the vertical array installed in the Te Puni building in Wellington, New Zealand, as part of the GeoNet building instrumentation programme. Co-seismic variations of pulse wave velocity and fundamental frequency are analysed and interpreted through a Timoshenko beam-like building model. This study shows that even though no structural damage was visually reported over the considered time of monitoring, co- and post-seismic variation of both parameters’ values are observed for almost all earthquakes, including a permanent shift following strong ground shaking. Variations of pulse-wave velocity and resonance frequency are cross-interpreted in terms of the building model. They reflect a time variant building response, correlated with the seismic loading. In addition, time delay of the pulse-wave velocity as a function of the building height provides relevant information on the location of the changes and confirms the efficient cross-interpretation of both methods for seismic Structural Health monitoring.

Method of estimation of frequency variation relying on estimation of shift of spectral peaks

Problem of estimation of variated frequency of components of polyharmonic signals has been arose. Three-dimensional time-frequency representation of signals is usually used to resolve this problem. But simple and reliable method of instantaneous frequency tracking is needed. Frequency tracking method based on estimation of shifts of peaks of spectrogram has been proposed in this paper. It is assumed that shift of spectral peaks of components of signal is proportional to variation of fundamental frequency. Logarithmic scaling of time-frequency representation is used to make spectral peaks equidistant. Temporal dependence of shift of spectral maximums is obtained using correlation of windowed spectrum at the first frame and spectrum of signal in the current window. Then obtained track is translated in linear scale. Proposed method does not estimate values of instantaneous frequency or central frequency of signal component but estimates its variation. Advantage of the method is that it can estimate frequency track even if range of frequency variation and its central value are known roughly or unknown at all. Multiple components do not interfere to estimate fundamental frequency variation. Reduction of bandwidth is recommended to increase accuracy of frequency track estimation, but analysis of time-frequency representation containing a few components is also possible. Dependency of performance of analysis of synthetic signals using the method on various signal to noise ratios under different conditions was estimated. Applicability of the method for vibrational diagnosing of rotary equipment was checked out using spectral interference method.

A Mandarin Chinese Reading Passage for Eliciting Significant Vocal Range Variations

Purpose There is a lack of standardized Mandarin reading text material that could potentially elicit significant variations in fundamental frequency (F0) and in vocal intensity for clinical voice evaluation. In this study, a phonetically balanced "Three Bears Passage" was developed based on the classical "Goldilocks" story for this purpose. The hypothesis was that the vocal range (F0 range and Intensity range) elicited while reading aloud the passage could be similar to that of the voice range profile (VRP) obtained with sustained vowel production and significantly different from that while reading an existing standard Mandarin passage. Method One hundred twenty young adults (60 men and 60 women, aged 25.22 ± 3.74 years) without vocal pathologies and vocal training participated in the study. Vocal range data, including F0-related measures and intensity-related measures, were obtained with Praat in order to construct VRPs for the sustained /a/ and to construct speech range profiles for passage reading. Results F0 range and intensity range for the new passage were significantly larger than those for the existing Mandarin passage for both male and female participants. In particular, the F0 range for the passage was not significantly different from that of the VRP for male participants. Conclusions These findings suggested that the new passage could allow individuals without vocal training to demonstrate a large vocal range in both F0 and vocal intensity, in a passage reading setting in a relatively short time. Further studies should be pursued with the passage to investigate the vocal range and vocal potential of individuals with voice disorders.

The Relationship Between Voice Onset Time and Increase in Vocal Effort and Fundamental Frequency.

Purpose Prior work suggests that voice onset time (VOT) may be impacted by laryngeal tension: VOT means decrease when individuals with typical voices increase their fundamental frequency (f o) and VOT variability is increased in individuals with vocal hyperfunction, a voice disorder characterized by increased laryngeal tension. This study further explored the relationship between VOT and laryngeal tension during increased f o, vocal effort, and vocal strain. Method Sixteen typical speakers of American English were instructed to produce VOT utterances under four conditions: baseline, high pitch, effort, and strain. Repeated-measures analysis of variance models were used to analyze the effects of condition on VOT means and standard deviations (SDs); pairwise comparisons were used to determine significant differences between conditions. Results Voicing, condition, and their interaction significantly affected VOT means. Voiceless VOT means significantly decreased for high pitch (p < .001) relative to baseline; however, no changes in voiceless VOT means were found for effort or strain relative to baseline. Although condition had a significant effect on VOT SDs, there were no significant differences between effort, strain, and high pitch conditions relative to baseline. Conclusions Speakers with typical voices likely engage different musculature to increase pitch than to increase vocal effort and strain. The increased VOT variability present with vocal hyperfunction is not seen in individuals with typical voices using increased effort and strain, supporting the assertion that this feature of vocal hyperfunction may be related to disordered vocal motor control rather than resulting from effortful voice production.

Cry features of healthy neonates who passed their newborn hearing screening vs. those who did not

ObjectivesTemporal and fundamental frequency (fo) variations in infant cries provide critical insights into the maturity of vocal control and hearing performances. Earlier research has examined the use of vocalisation properties (in addition to hearing tests) to identify infants at risk of hearing impairment. The aim of this study was to determine whether such an approach could be suitable for neonates. MethodsTo investigate this, we recruited 74 healthy neonates within their first week of life as our participants, assigning them to either a group that passed the ABR-based NHS (PG, N = 36) or a group that did not, but were diagnosed as normally hearing in follow-up check at 3 months of life, a so-called false-positive group (NPG, N = 36). Spontaneously uttered cries (N = 2330) were recorded and analysed quantitatively. The duration, minimum, maximum and mean fo, as well as two variability measures (fo range, fo sigma), were calculated for each cry utterance, averaged for individual neonates, and compared between the groups. ResultsA multiple analysis of variance (MANOVA) revealed no significant effects. This confirms that cry features reflecting vocal control do not differ between healthy neonates with normal hearing, irrespective of the outcome of their initial NHS. ConclusionsHealthy neonates who do not pass the NHS but are normal hearing in the follow-up (false positive cases) have the same cry properties as those with normal hearing who do. This is an essential prerequisite to justify the research strategy of incorporating vocal analysis into NHS to complement ABR measures in identifying hearing-impaired newborns.

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 (fo) 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 (sfo) and its standard deviation (sfoSD), fo derivative (dfo) and fo 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 dfo. 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.

Testosterone therapy masculinizes speech and gender presentation in transgender men

Voice is one of the most noticeably dimorphic traits in humans and plays a central role in gender presentation. Transgender males seeking to align internal identity and external gender expression frequently undergo testosterone (T) therapy to masculinize their voices and other traits. We aimed to determine the importance of changes in vocal masculinity for transgender men and to determine the effectiveness of T therapy at masculinizing three speech parameters: fundamental frequency (i.e., pitch) mean and variation (fo and fo-SD) and estimated vocal tract length (VTL) derived from formant frequencies. Thirty transgender men aged 20 to 40 rated their satisfaction with traits prior to and after T therapy and contributed speech samples and salivary T. Similar-aged cisgender men and women contributed speech samples for comparison. We show that transmen viewed voice change as critical to transition success compared to other masculine traits. However, T therapy may not be sufficient to fully masculinize speech: while fo and fo-SD were largely indistinguishable from cismen, VTL was intermediate between cismen and ciswomen. fo was correlated with salivary T, and VTL associated with T therapy duration. This argues for additional approaches, such as behavior therapy and/or longer duration of hormone therapy, to improve speech transition.

Freeze\u2013Thaw Resistance of Ternary Blended Concrete Using Ferronickel Slag

The present study investigated the resistance of concrete blended with ground granulated blast furnace slag (GGBS) and ferronickel slag (FNS) to cycles of freeze and thaw. The replacement ratio of the binders was 0%, 50 wt% of GGBS and 30 wt% of GGBS + 20 wt% of FNS for O100, OG50 and OG30F20, respectively. Specimens consisted of cement paste and concrete kept at 0.45 water/binder ratio. After 28 days of curing, specimens were subjected to freeze and thaw cycles (300) for measuring the variation of strength, weight loss and fundamental transverse frequency. Simultaneously mercury intrusion porosimetry was performed to examine the pore structure modifications at 28 days. The hydration products for cement paste cured at each determined age were characterized by X-ray diffraction and the content of CH and CSH was obtained from thermogravimetric analysis (TGA). As a result, the ternary blended concrete specimens showed lower deterioration degree when subjected to the freeze and thaw cycles. This may be due to a latent hydraulic and/or pozzolanic reaction producing more CSH in the matrix, which in turn increases the volume of small pores. The increased content of C–S–H gel for OG30F20 was confirmed by TGA, accounting for 69.9%. However, the binder system consisting of ordinary Portland cement and GGBS did not exhibit higher resistance to the given deleterious environment, presumably due to a delayed hydration process.

Older Listeners' Perception of Speech With Strengthened and Weakened Dynamic Pitch Cues in Background Noise.

Purpose Dynamic pitch, which is defined as the variation in fundamental frequency, is an acoustic cue that aids speech perception in noise. This study examined the effects of strengthened and weakened dynamic pitch cues on older listeners' speech perception in noise, as well as how these effects were modulated by individual factors including spectral perception ability. Method The experiment measured speech reception thresholds in noise in both younger listeners with normal hearing and older listeners whose hearing status ranged from near-normal hearing to mild-to-moderate sensorineural hearing loss. The pitch contours of the target speech were manipulated to create four levels of dynamic pitch strength: weakened, original, mildly strengthened, and strengthened. Listeners' spectral perception ability was measured using tests of spectral ripple and frequency modulation discrimination. Results Both younger and older listeners performed worse with manipulated dynamic pitch cues than with original dynamic pitch. The effects of dynamic pitch on older listeners' speech recognition were associated with their age but not with their perception of spectral information. Those older listeners who were relatively younger were more negatively affected by dynamic pitch manipulations. Conclusions The findings suggest the current pitch manipulation strategy is detrimental for older listeners to perceive speech in noise, as compared to original dynamic pitch. While the influence of age on the effects of dynamic pitch is likely due to age-related declines in pitch perception, the spectral measures used in this study were not strong predictors for dynamic pitch effects. Taken together, these results indicate next steps in this line of work should be focused on how to manipulate acoustic cues in speech in order to improve speech perception in noise for older listeners.

Masculine Voices Predict Attachment Style and Relationship Communication Patterns in Romantic Relationships

Humans exhibit sexually-based vocal dimorphisms, providing information about peoples’ intrinsic states. Studies indicate that voice pitch predicts relationship quality; however, none have explored its effects on relationship maintenance. We explored the association between sexually dimorphic vocal properties [voice pitch, measured by fundamental frequency (F0) and F0 variation, the within-subject SD in F0 across the utterance (F0-SD)], attachment styles, and communication patterns among Chinese heterosexuals in romantic relationships. Men’s F0-SD positively correlates with constructive communication pattern and negatively correlates with avoidant attachment style. No significant correlations are found for women. These findings suggest that men with masculine voices are more avoidantly attached, using avoidant communications. Furthermore, they show that voice may play a crucial role in and be an important morphological index of human mating relationships.