Fundamental Frequency Parameters Research Articles

Face and Speech Emotion Recognition System

Abstract: Emotions serve as the cornerstone of human communication, facilitating the expression of one's inner thoughts and feelings to others. Speech Emotion Recognition (SER) represents a pivotal endeavour aimed at deciphering the emotional nuances embedded within a speaker's voice signal. Universal emotions such as neutrality, anger, happiness, and sadness form the basis of this recognition process, allowing for the identification of fundamental emotional states. To achieve this, spectral and prosodic features are leveraged, each offering unique insights into the emotional content of speech. Spectral features, exemplified by the Mel Frequency Cepstral Coefficient (MFCC), provide a detailed analysis of the frequency distribution within speech signals, while prosodic features encompass elements like fundamental frequency, volume, pitch, speech intensity, and glottal parameters, capturing the rhythmic and tonal variations indicative of different emotional states. Through the integration of these features, SER systems can effectively simulate and classify a diverse range of emotional expressions, paving the way for enhanced human-computer interaction and communication technologies

Analysis of factors on voice quality in thyroidectomy patients.

Vocal cord paralysis (VCP) is a serious complication in thyroidectomy operations; however, its management remains unclear. The present study evaluated the voice parameters of patients who underwent surgery using Intraoperative Neurophysiologic Monitoring (IONM). A total of 52 patients (41 females and 11 males) who underwent a total thyroidectomy operation were evaluated using objective and subjective voice analysis examinations before and after surgery. Acoustic parameters, such as Fundamental Frequency (F0), Shimmer, Jitter, Noise-to-Harmonic ratio (NHR), and aerodynamic parameters, including S/Z ratio and maximum phonation time (MPT), were analyzed. Objective findings, including the VHI-10 (Voice Handicap Index) and V-RQOL (Voice-Related Quality of Life), were also analyzed. The relationship between voice parameters and IONM values was investigated. The objective analysis (acoustic and aerodynamic parameters) showed no difference (p>0.05). However, the subjective analysis, which involved the VHI-10 and V-RQOL measures, revealed a significant difference before and after the operation (p<0.05). The Spearman correlation analysis showed that the NHR postoperative 1st-month parameter negatively correlated (rho=-0.317, p<0.059), while the F0 postoperative 6th-month parameter positively correlated (rho=0.347) with the amplitude difference before and after dissection (Right R2-R1 difference) for the right RLN measured in IONM. Patients who are planning to undergo a thyroidectomy procedure should undergo voice assessment during both the preoperative and postoperative periods. IONM could improve voice quality outcomes.

Static Buckling and Free Vibration Analysis of Aligned CNTs Reinforced Composite Plates

This work introduces an analysis of the nonlinear buckling and free vibration behavior of polymer plates reinforced with aligned carbon nanotubes using Reddy's third-order shear deformation plate theory and incorporating Theodore von Kármán's geometric nonlinearity. The polymer plates were enhanced with single-walled carbon nanotubes assumed to exhibit either uniform distribution or functionally graded distribution across the thickness. The equations of motion were established through Hamilton’s principle and then solved by the Galerkin method and Airy’s stress function for the composite plates with fully simply supported edges. The investigation focused on assessing the effects of carbon nanotube distribution, volume fraction, and geometrical parameters on the buckling load and fundamental frequency parameters of composite plates through numerical results.&#x0D;

Application of modified first order shear deformation theory to vibration analysis of SSSS and CCSS thick anisotropic rectangular plates

This research presents a vibration analysis of a thick anisotropic rectangular plate using modified first shear deformation theory. Modified first shear deformation theory, which is not built upon the classical plate theory, was used to develop the kinematic equations and constitutive relations of a deformed section of thick anisotropic rectangular plate from which the generalized stress equations were determined. Using the assumptions of the theory, the strain energy and external work equations were formulated, and by employing the principles of total minimum potential energy, the total potential energy functional of a thick anisotropic plate was developed. Minimization of the total potential energy functional with respect to the deflection function (w) and with respect to the shear rotations (Φx) and (Φy) respectively, resulted in the governing differential equation and the two compatibility equations of the plate. The displacement functions that satisfy the governing and compatibility equations were obtained by solving the governing and compatibility equations. From the general displacement function, the peculiar deflection equations (shape functions) were obtained for the boundary conditions considered, which are simply supported on its four edges (SSSS), clamped on two adjacent edges, and simply supported on the other two (CCSS). Using the displacement equation and the equation for rotation in the x-direction (Φx) and equation for rotation in y-direction (Φy) the direct governing and two direct compatibility equations were obtained, from which coefficients that enable the formula for calculating fundamental natural frequencies to be obtained. For the boundary condition analyzed in this work, the stiffness coefficients (kR, kQ, kRQ, kq, kRRQ , kRQQ , kNR, kNQ, kNRQ and kλ ) were computed and used in determining the fundamental natural frequency parameter values at various span to depth ratios (5,10,20, 25 and 100), aspect ratios (1 to 2 at the increment of 0.1) and angle of fibre orientation (0o, 15o, 45o). The solutions of this study were compared with those from previous researchers. The fundamental natural frequency parameter values obtained in this study were compared with the work of Reddy (1984) for 0o angle of fibre orientation at span to depth ratios of 5,10, 20, 25, 50 and 100 at an aspect ratio of 1. The percentage difference values were 6.073%, 3.197%, 1.132%, 0.788%, 0.255%, and 0.112%, respectively. These differences revealed the closeness of the results of this present study to the results of Reddy (1984). This shows that the present theory provides good and acceptable solutions to the vibration problems of thick anisotropic rectangular plates.

Efficacy of voice therapy in the treatment of mutational falsetto

Objectives: This study aimed to evaluate the effectiveness of voice therapy in patients with mutational falsetto with objective and subjective methods. Patients and Methods: In this retrospective study, 18 male patients (mean age: 17.2±3.7 years; range, 14 to 26 years) diagnosed with mutational falsetto underwent acoustical analysis between May 2020 and January 2023 using Praat software. For objective acoustic analyses, fundamental frequency, jitter, shimmer, and maximum phonation time parameters were used. For subjective analyses, the GRBAS (Grade, Roughness, Breathiness, Asthenia and Strain) scale and the voice handicap index were used. Pre- and post-voice therapy subjective and objective parameters were compared. Results: The mean pre-voice therapy fundamental frequency value of the patients was 183.63±22.18 Hz, while the post-therapy value was 125.03±15.52 Hz. The mean pre-voice therapy voice handicap index score of the patients was 30.33±3.67, whereas the post-therapy score was 9.77±2.48. While the GRBAS scale value of the patients was 7.38±1.24, post therapy score was 1.55±1.29. As a result of the comparison of the objective and subjective values before and after the therapy, a statistically significant difference was found (p&lt;0.001). Conclusion: Mutational falsetto can be treated with the use of inexpensive sound analysis programs that do not require special hardware in clinical practice and with sound therapy methods.

Beyond (the cave of) pitch/loudness-equalization: A Commentary on Reymore (2021)

Traditional approaches in timbre research have often equalized sounds according to pitch, loudness, duration in order to study timbral differences across instruments. In a compact case study of the semantic qualities of the oboe and French horn, Reymore (2021) takes a different approach and considers timbral differences within musical instruments, which arise due to the covariation of timbre with the musical parameters of fundamental frequency (pitch) and playing effort (dynamic level). The study constitutes a timely contribution to a growing body of work on the covariation between timbre, pitch, and loudness. After providing a background and summary of important aspects of the target article, I elaborate on results from a recent complementary study that analyzed acoustical signal properties regarding that matter. Finally, I address three important issues in this context that appear to be worthy of future research.

Influence of temperature and porosities on free vibration of a three-phase bidirectional functionally graded sandwich beam

Understanding the influence of practical factors on natural frequencies of beams play an important role in design of this structure. This article explores the influence of temperature and porosities on vibration characteristics of a sandwich beam made from a three-phase bidirectional functionally graded material (BFGSW beam) for the first time. The sandwich beam composed from a homogeneous core and two face layers made of a three-phase composite material. The material properties are graded in both the beam axis and thickness by power-law functions, and they are evaluated by using the Voigt model. Heat loading with uniform temperature rise and even distribution of porosities are also considered. The expressions of the elastic strain energy and the kinetic energy for the beam as well as the strain energy due to temperature are obtained in the framework of the hyperbolic shear deformation theory. A two-node beam element with eight degrees of freedom has been proposed and used to establish the discretized equation of motion for the beam. The proposed method is validated by comparing the fundamental frequency parameters with two previous works. The beam with simply supported ends are used in numerical studies. The convergence of the derived beam element is represented by evaluating the fundamental frequency parameters. The effects of the temperature rise, the porosity volume fraction, the material indexes, the length to height ratio as well as the beam layer thickness ratio on the vibration characteristics are investigated and discussed in detail. It is concluded that the BFGSW beam parameters, the temperature rise and porous parameter play an important role in the natural frequency, which is helpful for the design of beam – like structures with the desired natural frequency.

Study on fundamental damped frequency parameters of plates made of FG porous material: a close-form solution

In this article, the natural frequencies of viscoelastic annular plates made of functionally graded porous (FGP) materials with assorted boundary conditions are investigated in a closed-form solution for the first time. The porosity variation is a function of the plate thickness according to symmetric and asymmetric distributions. The governing motion equations are derived by considering the first-order shear deformation theory (FSDT), energy method, and the calculus of variations. The viscoelastic properties of the structure are also captured by means of the standard linear solid (SLS) model. The equations of motion, which are a system of partial differential equations with variable coefficients, are then solved using the perturbations methodology. To do so, the equations with variable coefficients are converted to a system with constant coefficients, and the natural frequencies are found analytically in a closed-form solution without any approximation. In addition, a user-defined field (USDFLD) code is developed, which introduces solution-dependent material properties in Abaqus/Standard analyzes, for evaluating the accuracy of the analytical results. Finally, the impact of various parameters including inner-to-outer radius ratios, thickness-to-radius ratios, porosity coefficient, damping exponent, different combinations of boundary conditions, and porosity patterns on the natural frequencies of annular plates are examined.

European-native vocalizing: sex and age-class acoustic variation in the Central European red deer (Cervus elaphus)

Abstract Within-population acoustic variation of European red deer Cervus elaphus follows two empirically established common rules: Rule 1: suggesting similar-pitched stag and hind calls because of potential prevalence of natural over sexual selection on call pitch; and Rule 2: predicting lower-pitched calls in adults, because larger vocal folds normally produce lower-pitched calls in mammals. We found that both rules were supported for native Pannonian red deer from Central Europe. All fundamental frequency () parameter values of hind contact calls (for the exclusion of the beginning ) were indistinguishable from those of stag rutting roars. These results agree with published data on vocalization of male and female American and Asian wapiti Cervus canadensis. Calls of adults of either sex were lower in frequency than calf calls. These results disagree with data collected from adult and young American wapiti producing same-frequency calls, probably because of a distinctive mechanism of sound production (whistling).

Objective and subjective voice evaluation in Covid 19 patients and prognostic factors affecting the voice

Coronavirus disease 2019 (COVID-19), a respiratory and systemic zoonosis form caused by a virus belonging to the Coronaviridae family. Although several studies have shown the otolaryngology symptoms are affected in COVID-19 patients, the number of studies regarding the COVID-19 effects on voice is limited. Our study aims to evaluate the effect of COVID-19 on voice objectively - subjectively and compare it with the control group. 50 hospitalized patients with laboratory-confirmed COVID-19 and 50 healthy individuals were included in the study as study and control group, respectively. All subjects were trained to vocalize a continuous/a/ vocal pattern at speech sound intensity for Maximum Phonation Time. Voice samples were recorded using a Sony (ICD-PX470) audio recorder and analyzed by the Praat program. Dysphonia grades were ranked on 4-point scales (grade: 0=none; 1= mild; 2= moderate; 3=severe). It is seen from the results that, there were significant differences between the male and female participants in acoustic parameters of fundamental frequency (F0) (p&lt;0.001), shimmer and mean harmonic to noise ratio (HNR) (p=0.011). There was also a significant difference in F0 values of infected and healthy participants (p=0.008). However, there was no significant interaction between gender and health status in any acoustic parameters (p&gt;0.05). The degree of thoracic computed tomography (CT) involvement had no significant effect on parameters (p&gt;0.05), while there was a weak positive relationship between the duration of hospitalization and F0 (rs=0.397, p=0.004). Dysphonia was positively associated with health status (rs=0. 682, p&lt;0.001), and female infected participants reported more frequent dysphonia than males. In our study, we examined the effect of COVID-19 on voice both objectively and subjectively and evaluated the relationship between CT involvement and duration of hospitalization, which made our study more reliable. Future studies with larger and more specific patient groups to investigate the relationship between COVID-19 and dysphonia will shed a light on the subject.

The effect of type 1 diabetes mellitus on voice in pediatric patients.

The aim of this prospective case-control study was to determine the effect on the voice of type 1 diabetes mellitus (T1DM) in paediatric patients. The study included patients aged 6-18years followed up for at least 1year because of T1DM, and a control group of age and gender-matched healthy volunteers. Following an Ear, Nose, and Throat (ENT) examination, all subjects underwent flexible endoscopic laryngeal examination. Fasting venous blood samples were taken in the morning for the examination of fasting blood glucose (FBG), HgbA1C, and kidney, liver, and thyroid function tests. Data were recorded from the patient files of age, gender, comorbidities, and the development of diabetes-related complications. Voice recordings were taken and the Voice Handicap Index (VHI)-10 form was completed. The patients and control group were compared in respect of the parameters of fundamental frequency, jitter, shimmer, and acoustic voice quality index (AVQI). Evaluation was made of 64 children and adolescents as 32 in the patient group (Group 1) and 32 healthy control subjects (Group 2). Group 1 comprised 17 females and 15 males with a mean age of 12.75 ± 3.23years. Group 2 comprised 17 females and 15 males with a mean age of 12.75 ± 3.33years. In Group 1, mean disease duration was 5.21 ± 3.17years (range, 1-13years), the FBG value was mean 216.6 ± 122.3mg/dl, mean HgbA1c was 10.7 ± 2.8, as ≤ 7 in 4 patients, 7-9 in 4, and > 9 in 24. Maximum phonation time (MPT) was determined as 10.66 ± 3.6 secs in Group 1 and 12.11 ± 4.43 in Group 2. VHI was determined as 2.33 ± 3 in Group 1 and 2.31 ± 2.77 in Group 2. No statistically significant difference was determined between the groups was determined in respect of acoustic analysis, perturbation parameters, AVQI and body mass index. This study is the first to have investigated the effects of T1DM on the voice in paediatric patients. The study results showed that the AVQI value was higher in the patient group but not to a statistically significant level. Therefore, there is a need for further studies with larger samples. The current study can be of guidance for further studies in this field.

Akustičke karakteristike glasa kod odraslih osoba sa depresivnim poremećajem

In order to examine the differences in people suffering from depression (EG, N=18) compared to the healthy controls (CG1, N=24) and people with the diagnosed psychogenic voice disorder (CG2, N=9), nine acoustic features of voice were assessed among the total of 51 participants using the MDVP software programme ("Kay Elemetrics" Corp., model 4300). Nine acoustic parameters were analysed on the basis of the sustained phonation of the vowel /a/. The results revealed that the mean values of all acoustic parameters differed in the EG compared to both the CG1 and CG2 as follows: the parameters which indicate frequency variability (Jitt, PPQ), amplitude variability (Shim, vAm, APQ) and noise and tremor parameters (NHR, VTI) were higher; only the parameters of fundamental frequency (F0) and soft index phonation (SPI) were lower (F0 compared to CG1, and SPI compared to CG1 and CG2). Only the PPQ parameter was not significant. vAm and APQ had the highest discriminant value for depression. The acoustic features of voice, analysed in this study with regard to the sustained phonation of a vowel, were different and discriminant in the EG compared to CG1 and CG2. In voice analysis, the parameters vAm and APQ could potentially be the markers indicative of depression. The results of this research point to the importance of the voice, that is, its acoustic indicators, in recognizing depression. Important parameters that could help create a programme for the automatic recognition of depression are those from the domain of voice intensity variation.

Analysis of trypsin activity at β-casein layers formed on hydrophobic surfaces using a multiharmonic acoustic method.

Proteolysis of milk proteins, such as caseins, caused by milk proteases, can change the organoleptic and nutritional characteristics of milk, and therefore it is essential to monitor this enzymatic activity. We used trypsin as a model protease because of its role as a biomarker for pancreatitis. The aim of this work was to demonstrate the detection of proteolysis of β-casein by trypsin using a multiharmonic quartz crystal microbalance (QCM) biosensor. The β-casein layer was deposited from a 0.1 mg mL-1 solution on a hydrophobic surface consisting of a self-assembled monolayer of 1-dodecanethiol on the gold electrode of the QCM. The addition of an increasing concentration of trypsin leads to the removal of the casein layer due to proteolysis, and correlates with an increase in the resonant frequency of the QCM. We investigated the effect of trypsin concentrations (0.3-20 nM) on the kinetics of the proteolysis of β-casein and demonstrated that the frequency increase is proportional to the protease concentration. Consequently, an inverse Michaelis-Menten model was used to estimate the Michaelis-Menten constant (KM = 0.38 ± 0.02 nM) and the limit of detection (LOD = 0.16 ± 0.02 nM). The thickness, mass and viscoelastic properties of the protein adlayer after its formation and following the proteolytic cleavage were evaluated by means of multi-harmonic analysis. We found that β-casein is preferably adsorbed on the hydrophobic surfaces as an asymmetrical double layer, of which the innermost layer was found to be denser and thinner (about 2.37 nm) and the outermost layer was found to be less tightly bound and thicker (about 3.5 nm).

How king penguins advertise their sexual maturity

Reproductive success can improve with experience, which increases with age in many long-lived species. Signals that provide reliable information about age are therefore of importance for mate choice and consequently are under sexual selection. In birds, these are often vocal signals as well as visual signals in the form of plumage coloration. King penguins, Aptenodytes patagonicus, are sexually monomorphically ornamented seabirds that perform a complex visual and acoustic courtship display. Coloured beak spots and ear patches contain information about the condition and physiological status of adult males and females, but their role as a signal of age has previously only been studied in young birds. Vocalizations have mainly been studied as signals of individuality and not in the context of courtship. We investigated two multicomponent signals in the context of mate choice by analysing beak spot, ear patch and call parameters of wild king penguins. We explored the relation between these signals and age as well as age classes (chicks, juveniles, adults). Ornament parameters were weakly correlated with in males, but not in females, while acoustic parameters were highly correlated with age in both sexes. The calls' fundamental frequency and energy parameters and all the beak spot parameters reliably classified individuals into their age class. Since age class was redundantly encoded in both acoustic and colour parameters, we hypothesize that calls and ornaments function as back-up signals that increase the chance of accurately conveying the age class of the sender to receivers. King penguins might sequentially analyse age class signals during courtship, where acoustic signals serve as long-range communication when sender and receiver are out of sight, and ornamentation signals become important at close range. We show the importance of considering bimodal, multicomponent signals when studying complex behaviour and discuss how signalling environment, the species' life history and mating system influence the evolution of communication signals.

Free vibration analysis of a rotating single edge cracked axially functionally graded beam for flap-wise and chord-wise modes

This study concerns with the free vibration analyses for centrifugally stiffened cracked beams modelled as functionally graded material in the axial direction. The variation of material properties along the cracked beam is expressed in terms of the power law distribution. Analyses are carried out by the Rayleigh–Ritz method that uses shape functions and energy expressions written for centrifugally stiffened Euler-Bernoulli beams. The influence of the hub radius, angular velocity, crack location to beam length ratio and crack depth to thickness ratio and cross-section size ratio and inhomogeneity on natural frequencies are examined for the beams with the clamped-free boundary condition. The results are verified by using the data available in the open literature and/or the outputs of finite element analyses performed for an axially functionally graded solid beam. The results show that the fundamental frequency parameters reduce with the increasing the ratio of crack depth to thickness. The highest natural frequency droop exists close to the root of the beam for flap-wise and chord-wise vibrations. Another important finding is that reduction of natural frequency parameters in chord-wise modes is larger than that in flap-wise modes when the crack location is varied. This new research should help to improve predictions of the impact of the crack on free vibrations for the rotating cracked axially functionally graded beams.

Soil non-homogeneity and soil-structure interaction effects on beam vibrations

This paper describes the effects of soil non-homogeneity, the soil–structure interaction and the two-parameter elastic foundation model on the free vibration of Euler–Bernoulli beams. Non-homogeneity of the soil foundation is described by parabolic variations of the two-parameter elastic soil foundation while Poisson's ratio is assumed to remain constant. Hence, the soil–structure interaction is quantified using a relative ratio of beam and soil foundation properties. The equation of motion including the previous effects is derived and the fundamental frequency parameters are computed. The influence of the above parameters on the free-vibration characteristics of the beam is investigated. The results obtained from this analytical method for a simply supported beam were found to be in very good agreement with data from the literature.

Vibration of two types of porous FG sandwich conical shellwith different boundary conditions

In this paper, in various boundary conditions, the vibration behavior of the two types of porous FG truncated conical sandwich shells is investigated based on the improved high order sandwich shells theory. Two types of porosity are considered in the power law rule to model the FGM properties. In the first type, FG face sheets cover a homogeneous core, and in the second one, the FG core is covered by the homogeneous face sheets. All materials are temperature dependent. By utilizing the Hamilton's energy principle, using the nonlinear von Karman strains in the layers and considering the in-plane stresses and thermal stresses in the core and the face sheets, the governing equations are obtained. A Galerkin method is used to solve the equations with clamped-clamped, clamped-free, and free-free boundary conditions. To validate the results, a FEM software is used and some results are validated with the results in the literatures. Also, Some geometrical parameters, temperature variations and porosity effects are studied. By increasing the length to thickness ratio, temperature, the semi-vertex angle and the radius to thickness ratio, the fundamental frequency parameter decreases in all boundary conditions. In both types of sandwiches for both porosity distributions, by increasing the porosity volume fraction, the fundamental frequency parameters increase. Frequency variation of type-II is lower than type-I in the thermal conditions. And the fundamental frequencies of the clamped-clamped (CC) and clamped-free (C-F) boundary conditions have the highest and lowest values, respectively.

Ascending tones as signifiers of cultural identity in northern England

This study investigates prosodic patterns in dialects of Manchester, Liverpool, Newcastle and Leeds that distinguish northern English pronunciation from other regional types. The authors argue that melodic cues can act as signifiers of northern English cultural identity. The empirical research included auditory and acoustic analyses of authentic speech recordings of four female and four male speakers from the listed above urban centres in northern England. The research primarily concerned intonational means and prosodic parameters of fundamental frequency (F0) and pitch range. The findings revealed both individual characteristics of each dialect and regional distinctive features common for northern speech in general with a special regard to intergender variation. The results of the research showed that the distribution of melodic patterns in northern English speech is different from the standard British pronunciation and is mainly characterized by the frequent use of rising contours in affirmative utterances. The detailed acoustic analysis of configuration and pitch range of such ascending tunes allowed the authors to describe four main variants of rising intonation in final sense-groups of declaratives. These specific melodic cues of oral speech make it possible to identify a northerner and take into account this sociocultural context, as well as other conventional implicatures in the process of cross-cultural verbal interaction.

Implementation of xgboost for classification of parkinson’s disease

Parkinson’s Disease (PD) is an advanced neurodegenerative illness. It is about 90% of PD sufferer shows speech disorders in the initial stages. Hence, in this research, speech features were applied to classify this illness. The most famous speech features used in PD research are jitter, shimmer, fundamental frequency parameters, harmonicity parameters, Recurrence Period Density Entropy (RPDE), Detrended Fluctuation Analysis (DFA), and Pitch Period Entropy (PPE).Those features were then called as baseline features used in this research. In this research, the XGBoost algorithm was used for the classification of PD. Initially, the whole baseline features were used in the XGBoost algorithm and obtained an accuracy score of the model 84.80%. For improving the model, feature selection was performed by plotting feature importance, which causes features of locShimmer (Fscore = 3) was excluded from the model. After feature selection was performed, the accuracy score of the model has increased to 85.60 %. We tried to improve the model using for second features selection, by excluding features with F-score values less than 20. However, after performed this feature selection, the accuracy of the model was decreased to 84.40 %. Thus, the model used is the model with an accuracy of 85.60%.

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.