Acoustic Quality Research Articles

Acoustic roughness measurement of railway tracks: Implementation of an optical measurement approach & possible improvements to the standard

The measure for assessing the acoustic quality of the rail surfaces, the acoustic roughness, is defined in the EN 15610 standard. It is shown that this standard contains gaps with regard to the applied procedures for processing the raw data to the quantity of acoustic roughness. Additions to the standard appear necessary to ensure better comparability of the results. A piece of rail tactilely measured by METAS (Swiss Federal Institute of Metrology) was used as a reference. Measurement data recorded by a laser triangulation sensor was used to quantify the adjustments to the standard. This paper provides an overview of the individual processing steps and systematically examines possible additions to the standard to improve the quality of the outcome. Special emphasis was given to a method for outlier removal, pre-filtering, spike removal, curvature correction and calculation of one-third octave bands. It becomes apparent that different implementations can have a significant impact on the final result. The filter used, the wavelength ranges, the methodology for removing outliers should be specified. The spike removal, curvature correction and the calculation of the one-third octave bands should be supplemented in detail to reduce ambiguities in the implementation.

Development of a BIM-Based Framework Using Reverberation Time (BFRT) as a Tool for Assessing and Improving Building Acoustic Environment

Both the building design and the construction process determine the indoor acoustic quality of enclosures. A suitable indoor acoustic environment is crucial for the productivity and well-being of users. For this purpose, Reverberation Time (RT) is often calculated or measured in situ. Recently, Building Information Modelling (BIM) has provided a new paradigm to face building projects. Nevertheless, little research has been conducted on the optimisation of indoor acoustics using BIM methodology. In this context, the objective of this work is to propose and develop a BIM-based framework for the analysis, evaluation and optimization of the RT. The proposed procedure allows designers to explore alternatives in order to achieve an adequate acoustic performance without any further needs of specific software. This proposal is devised to consider some important characteristics of the project, such as its location, applicable regulations, room uses, materials and costs. This framework calculates the solution set that meets the requirements, showing the set of optimal solutions according to the minimization of both the cost and the optimum absorbent surface area. BFRT contributes by offering a tool to support the decision making process of designers during the initial design phase in the field of acoustic conditioning of buildings.

Implementing a Statistical Parametric Speech Synthesis System for a Patient with Laryngeal Cancer.

Total laryngectomy, i.e., the surgical removal of the larynx, has a profound influence on a patient’s quality of life. The procedure results in a loss of natural voice, which in effect constitutes a significant socio-psychological problem for the patient. The main aim of the study was to develop a statistical parametric speech synthesis system for a patient with laryngeal cancer, on the basis of the patient’s speech samples recorded shortly before the surgery and to check if it was possible to generate speech quality close to that of the original recordings. The recording made use of a representative corpus of the Polish language, consisting of 2150 sentences. The recorded voice proved to indicate dysphonia, which was confirmed by the auditory-perceptual RBH scale (roughness, breathiness, hoarseness) and by acoustical analysis using AVQI (The Acoustic Voice Quality Index). The speech synthesis model was trained using the Merlin repository. Twenty-five experts participated in the MUSHRA listening tests, rating the synthetic voice at 69.4 in terms of the professional voice-over talent recording, on a 0–100 scale, which is a very good result. The authors compared the quality of the synthetic voice to another model of synthetic speech trained with the same corpus, but where a voice-over talent provided the recorded speech samples. The same experts rated the voice at 63.63, which means the patient’s synthetic voice with laryngeal cancer obtained a higher score than that of the talent-voice recordings. As such, the method enabled for the creation of a statistical parametric speech synthesizer for patients awaiting total laryngectomy. As a result, the solution would improve the quality of life as well as better mental wellbeing of the patient.

Lute Acoustic Quality Evaluation and Note Recognition Based on the Softmax Regression BP Neural Network

Note recognition technology has very important applications in instrument tuning, automatic computer music recognition, music database retrieval, and electronic music synthesis. This paper addresses the above issues by conducting a study on acoustic quality evaluation and its note recognition based on artificial neural networks, taking the lute as an example. For the acoustic quality evaluation of musical instruments, this paper uses the subjective evaluation criteria of musical instruments as the basis for obtaining the results of the subjective evaluation of the acoustic quality of the lute, similar to the acoustic quality evaluation, extracts the CQT and MFCC note signal features, and uses the single and combined features as the input to the Softmax regression BP neural network multiclassification recogniser; the classification coding of standard tones is used as the target for supervised network learning. The algorithm can identify 25 notes from bass to treble with high accuracy, with an average recognition rate of 95.6%; compared to other recognition algorithms, the algorithm has the advantage of fewer constraints, a wider range of notes, and a higher recognition rate.

Evaluation of Voice After Open Airway Surgery in Children: A Systematic Review.

ObjectiveThis review aims to describe the methods used to assess the vocal quality and quality of life of children after airway reconstruction and their limitations.Data SourcesA systematic review was carried out in 10 databases for articles published between 2000 and 2021 following the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses).Review MethodsArticles were included that described perceptual voice assessment with or without acoustic measures and/or voice quality impact questionnaires. Articles with no description of a specific voice assessment were excluded.ResultsA total of 12 studies were included, yielding 263 patients. The mean age at evaluation was 9 years. Follow-up varied from 5 months to 20 years with most patients being evaluated at least a year after surgery. Methods used to evaluate voice were perceptual, aerodynamic, and acoustic analysis and quality of life questionnaires. CAPE-V (Consensus Auditory Perceptual Evaluation–Voice) was the most used auditory-perceptual instrument (72.7%). Of the acoustic parameters, fundamental frequency and maximum phonation time were the most described (58.3%), and among the quality of life assessment questionnaires, pVHI (Pediatric Voice Handicap Index) was the most used (54.5%).ConclusionMultidimensional evaluations tailored to the individual child can be recommended after open airway surgery. CAPE-V scale, fundamental frequency, maximum phonation time, and pVHI are the most frequently used methods; therefore, their use may help broaden communication among authors. In the multitude of methods available, cognitive ability and degree of voice disturbance should be considered since they are the most important limiting factors in this population.

The Acoustic Voice Quality Index (AVQI) in People with Parkinson's Disease Before and After Intensive Voice and Articulation Therapies: Secondary Outcome of a Randomized Controlled Trial

The majority of individuals with Parkinson's disease (PD) experience voice and speech problems during the course of the disease. Despite the importance of voice quality in communication and the documented disordered voice quality in PD, few studies have explored the effects of speech treatment on this variable. A parallel arm, unblinded randomized controlled trial (RCT) was conducted with two active comparators, LSVT LOUD (n=23) and LSVT ARTIC (n=20), and an inactive comparator group of untreated individuals with PD (n=22). A group of 20 healthy adults was also included for pre-treatment analysis. Voice recordings were obtained pre-treatment, immediately post-treatment and at 6-month follow-up. The acoustic voice quality index (AVQI) is reported here as a secondary outcome measure of the RCT. Linear mixed-effects regression analysis was performed with AVQI and sound pressure level (SPL) as dependent variables. Pearson correlation coefficient analysis was also conducted to explore the relationship between voice quality and SPL. Statistically significant improvements in AVQI and SPL from pre-treatment to post-treatment and follow-up were only observed in the LSVT LOUD group. Voice quality significantly improved only from pre-treatment to follow-up in the LSVT ARTIC group, whilst significant improvements in SPL were observed during maximum phonation only immediately post-treatment. No significant changes were observed in the untreated group. This study investigated the effects of intensive speech treatment targeting voice or targeting articulation on voice quality, as measured by the AVQI, in individuals with PD. Findings indicate that voice-focused treatment leads to greater improvements in voice quality in this population.

The effect of acoustic quality on work productivity and psychosocial stress levels in the basement lobby area

The basement lobby area in Campus II of Universitas Atma Jaya Yogyakarta was originally designed to function as a vehicle parking and laboratory space with noise-generating equipment, but it is currently being used as a place for students to do assignments. Meanwhile, it has been discovered that psychosocial stress can be caused by continuous exposure to noise, thereby, making it necessary to consider the quality factor of the indoor environment of this area for students use. Therefore, this study was conducted to determine the effect of the noise in the basement lobby area on student work productivity and psychosocial stress. This involved the use of a quantitative method by measuring the noise level using Phonic PAA3 per one point in the 4 segments of the corridor according to the provisions of SNI 7231:2009. Moreover, a qualitative approach was also applied by distributing online and offline questionnaires to determine the perception of noise, psychosocial stress, and its effect on work productivity. A total of 109 respondents consisting of 48 architecture, 40 civil engineering, and 21 techno-biology students using the lobby as a place to do assignments were used as the respondents. The data obtained were analyzed using a simple regression method in the SPSS25 program. It is important to note that the quantitative and qualitative measurements were not conducted simultaneously. The results showed that the study room does not fulfill the standard reference value of 45dB required for the noise level as indicated by the highest and lowest noise (Leq) values recorded to be 74.10dB and 64.34dB in segments B and A, respectively, as well as the overall average of 70.1dB. Furthermore, the combination of the qualitative and quantitative data showed that the noise affects students' psychosocial stress by 43% and productivity by 45%, hence, this means the noise reduced the student productivity. Therefore, the noise factor needs to be considered in planning a workspace or converting the function of space in order to ensure its purpose is achieved maximally.

14. Interdisciplinary Approach to Assessing the Acoustic Quality of Violins

Abstract The paper presents the interdisciplinary approach to assessing the acoustic quality of violins through a survey addressed to specialists in the field of music - instrumentalists, teachers, artists. Violins with modified geometric parameters in intermediate stages from a technological point of view were investigated, respectively unfinished violins (in white). The aim of the study was to classify the musical instruments heard according to five acoustic criteria considered relevant for violinists. Criteria such as: bright tone, clarity of sounds, warm/silky sound, amplitude of sounds and equal sound on all 4 strings were also established through a survey of artistic impressions among specialists, in a stage prior to the study presented in this article.

Main acoustic attributes and optimal values of acoustic parameters in Peking opera theaters

To perfect the audience's enjoyment of Peking opera performance in modern theaters, the present study set out to identify the main subjective attributes for good acoustic quality of Peking opera and find out the optimal values of correlated acoustic parameters. Firstly, the importance of the subjective attributes was evaluated through a social survey by audience in Peking opera theaters. Then, the correlated acoustic parameters were identified. Lastly, in order to obtain optimal values of the acoustic parameters, subjective preference tests were conducted and the factors influencing the preference scores were also investigated. The social survey revealed that the most valued acoustic attributes apart from the loudness were clarity and liveness of voice. The acoustic parameters correlated with the attributes were reverberation time, frequency characteristics of reverberation time and sound level. The subjective preference tests revealed the optimal value of occupied reverberation time was around 0.6 s. The optimal frequency characteristics of reverberation time was the one with more reverberation in higher frequencies. The optimal sound level for young group was 70–73 dBA. When comparing the experienced and young group, there was no significant difference in expectation in acoustic attributes. What was unique in young generation’ preference in acoustic parameters was that the optimal range of reverberation time was longer for young people (0.6–1.0 s) than it was for the experienced people (0.2–0.6 s). The present study will facilitate the construction of Peking opera theater with good acoustics and boost the revitalization of the cultural heritage.

Long-Term Quality of Life of Vestibular Schwannoma Patients: A Longitudinal Analysis.

Vestibular schwannoma management aims to maintain optimal quality of life (QoL) while preventing severe sequelae of the tumor or its treatment. This study assessed long-term QoL of patients with vestibular schwannoma in relation to treatment modality and decisional regret. A longitudinal study, in which clinical and QoL data were used that were cross-sectionally acquired in 2014 and again in 2020 from the same patient group. A tertiary expert center for vestibular schwannoma care in the Netherlands. QoL was measured by the Penn Acoustic Quality of Life (PANQOL) scale. Changes in time were assed using a linear mixed model. In addition, the Decision Regret Scale was analyzed. Of 867 patients, 536 responded (62%), with a median follow-up of 11 years. All PANQOL subdomain scores remained stable over time and did not exceed minimal clinically important difference (MCID) levels. Time since treatment did not affect QoL. Patients had comparable average QoL scores and proportions of patients with changing QoL scores (ie, exceeding the MCID) over time, irrespective of the received initial treatment. Female patients and those who required salvage therapy (either by radiotherapy or surgery) reported a lower QoL. The latter patient group reported the highest decisional regret. On average, the long-term QoL of patients with vestibular schwannoma is comparable for patients under active surveillance and those who have received active treatment, and it remains stable over time. This suggests that, on average, preservation of QoL of patients with vestibular schwannoma is feasible when adequately managed.

Music education in the digital age: Challenges associated with sound homogenization in music aimed at adolescents

Adolescent music preferences revolve around so-called popular music, specifically that which is highly manipulated by audio and music production technologies and aimed at the mass market. These processes can result in music genres that lean toward sound homogenization, a phenomenon that could gradually restrict adolescents’ access to the acoustic richness of other music styles that have emerged throughout history. The objective of this work was to analyze the music genres favored by a sample of Spanish adolescents ( n = 464), based on their acoustic qualities (timbre, rhythm, and dynamics). The results of the automatic analysis indicated a great deal of overlap in terms of sound, which corroborated the homogeneous character of the genres. This calls for an approach to secondary music education that helps preserve musical richness and stylistic variety in the classroom.

Comparison and Validation of Acoustic Voice Quality Index Version 2 and Version 3 among South Indian Population

Acoustic Voice Quality Index (AVQI) has emerged in the recent past as a robust multiparametric voice quality evaluation tool. Two versions of AVQI derived using the program PRAAT have found extensive clinical and research applications. These versions have been validated in several languages around the world. However, no research reports are available on validation of AVQI in the South Indian population. Further, studies comparing the performance of the two versions of AVQI are limited in the literature. This study was designed to validate and compare the two versions of AVQI (AVQIv02.02 and AVQIv03.01) in South Indian languages (Malayalam and Kannada). A retrospective analysis of previously recorded voice samples was carried out on a total of 160 (91 normophonic and 69 dysphonic) voice samples. These samples were perceptually rated on a GRBAS scale by five experienced speech-language pathologists. Standardized Syllable Number (SSN) necessary to derive AVQIv03.01 was computed. Following this, these samples were analyzed to obtain the AVQIv02.02 and AVQIv03.01. The concurrent validity and diagnostic accuracy of these measures were then examined and compared. A moderate agreement was obtained across the judges on perceptual evaluation of voice quality. SSN in Malayalam and Kannada languages were identified to be 29 and 25 syllables respectively. Language differences were not observed on both versions of AVQI. The concurrent validity of AVQIv03.01 (r = 0.788) was superior to that of AVQIv02.02 (r = 0.655). Further, the threshold of differentiating normophonic and dysphonic samples were determined to be >3.45 for AVQIv02.02 and >2.45 for AVQIv03.01. AVQIv03.01 is superior to AVQIv02.02 in terms of its diagnostic accuracy and concurrent validity. Current findings also extend the application of AVQI as a robust tool for the evaluation of voice characteristics to the South Indian population.

Methods for probability distributions estimation of indoor environmental parameters and long-term IEQ assessment

ABSTRACT To overcome the difficulties in comparing enormous time series for indoor environmental parameters and make use of technological developments in previous research, this study considers environmental parameters from a new perspective, their probability density functions (PDFs). PDFs are combined with existing indoor environmental quality (IEQ) mathematical models to assess the long-term IEQ. Two methodologies were developed: probability distribution estimation of indoor environmental parameters and long-term IEQ distribution assessment based on the Monte Carlo method. The effectiveness of the developed methodologies was illustrated in a three-month IEQ assessment of an office. PDFs were obtained with specific mathematical expressions for the three-month air temperature, sound level and illuminance. The three-month distributions for thermal, visual, acoustic and overall environmental quality were presented using eight previous IEQ mathematical models. PDFs have the advantage of using only a few main parameters instead of an enormous time series to explain the behaviour and characteristics of environmental parameters. PDFs can also potentially determine the commonalities of environmental distributions for different buildings. The obtained IEQ distributions present a straightforward and comprehensive impression of the long-term IEQ, rather than a simple index.

A REVIEW OF THE PSYCHOLOGICAL EFFECT OF ENVIRONMENTAL SOUND

Few studies have stressed how access to high-quality acoustic environment affects wellbeing, quality of life, and environmental health. The acoustic environment influenced by noise pollution reduces the restorative effect generated by the natural environment. Noise policies which focus on noise level as a determinant of wanted and unwanted sounds are inadequate to control the acoustic quality of the environment. Therefore, this paper aims to identify the psychological effect of environmental sound and the direction of study for environmental sound research from 1993 to 2020. Review works of literature were identified through multiple interdisciplinary health, environmental, and urban planning databases in available open access journals. The focus of the study will look into keywords of "environmental sound", "noise", “acoustic environment” and "mental health". The review showed that previous study focused on the negative effect of noise and noise mitigation methods through the noise level controls in the guidelines. On the other hand, recent reviews continue to discuss the impact of noise further and add on a positive view of the psychological effect of environmental sound. Noise mitigation methods also focused on enhancing positive sounds and methods for a more comprehensive study of the environmental sound.

Choral Conductors Vocal Loading in Rehearsal Simulation Conditions

Choir conductors represent a profession with an intensive vocal load. The present study aims to investigate the impact of 40 minutes vocal loading tasks on fundamental frequency (F0), jitter (Jitt), shimmer (Shim), median cepstral peak prominence (CPPs), and CPPs standard deviation in specific acoustic conditions. Eighteen amateur choir conductors (13 female, five male) participated in the study. The vocal loading experiment was organized in rooms where each conductor usually had choir rehearsals. The vocal loading experiment included vocal warm-up, singing, and loud reading. The STIPA test signal provided the background noise with 60 dBA @ 1m during the singing and reading tasks. The F0, Jitt, Shim, CPPs, and CPPs SD were extracted before and after vocal loading by the Vocal Holter Med (VHM) device. Additionally, Acoustic Voice Quality Index (AVQI) was estimated for participants, and all of them completed the Voice Handicap Index-30 (VHI-30) and the Singing Voice Handicap Index (SVHI). Finally, reverberation time (T30) was measured in each rehearsal room. A statistically significant decrease of CPPs SD by 0.1 dB was observed in male conductors. Associations between CPPs SD and VHI-30 (r = 0.789, P = 0.001) were found in female conductors, and between Jitt and SVHI (r = 0.9, P = 0.037) in male conductors. Female conductors with higher total score of SVHI demonstrated increase of postloading F0 (r = 0.612, P = 0.026). Forty-minute vocal loading tasks that included warm-up, intensive singing, and loud reading did not significantly impact vocal parameters in female and male conductors. In addition, the rehearsal room volume and length of reverberation time did not affect obtained vocal parameters after vocal loading.

AFExplorer: Visual analysis and interactive selection of audio features

Acoustic quality detection is vital in the manufactured products quality control field since it represents the conditions of machines or products. Recent work employed machine learning models in manufactured audio data to detect anomalous patterns. A major challenge is how to select applicable audio features to meliorate model’s accuracy and precision. To relax this challenge, we extract and analyze three audio feature types including Time Domain Feature, Frequency Domain Feature, and Cepstrum Feature to help identify the potential linear and non-linear relationships. In addition, we design a visual analysis system, namely AFExplorer, to assist data scientists in extracting audio features and selecting potential feature combinations. AFExplorer integrates four main views to present detailed distribution and relevance of the audio features, which helps users observe the impact of features visually in the feature selection. We perform the case study with AFExplore according to the ToyADMOS and MIMII Dataset to demonstrate the usability and effectiveness of the proposed system.

Evaluating the overall comfort of undergraduates by using the punishment substitution method

In this paper, the overall comfort of humans in thermal, light, acoustic and air quality environments was studied in a university classroom in Shanghai, and the actual overall comfort vote index was evaluated. The dimensionless function of each environmental evaluation index and human comfort level was established by a combination of subjective questionnaire assessment and objective parameter measurement, and the weight of each environmental evaluation index was obtained by the method of vector similarity. The overall comfort evaluation model was synthesized by using the punishment substitution method, dimensionless function and weight. The influence of different environmental combinations on the overall comfort evaluation model was explored, and the results indicated that the more a single evaluation index deviated from its comfort zone, the more obvious the change it caused in comprehensive comfort. The model can be used to adjust classroom environmental parameters to improve comprehensive comfort, and the results should provide a reference for evaluating the overall comfort of the classroom environment and a reasonable basis for classroom environment design parameters.

Effects of different environment combinations on the comfort and productivity of researchers in winter

Indoor environmental quality is considered an important indicator of the sustainable development of architecture. It not only reflects the comfort level of occupants in the building but also affects their productivity, particularly in research institutions. However, due to the inherent correlation among various environmental indexes, it is difficult to evaluate the influence of specific physical parameters on the occupant’s comfort and research performance. This paper is based on an experiment conducted in a controlled research office in a pharmaceutical research company in the Northeast of China. The controlled research office was equipped with a radiant floor heating system that supplied heating in winter. We recruited 32 researchers and divided them into four subgroups. Each subgroup of researchers was required to conduct daily research activities under 12 different environment combinations. Data were collected from physical environment measurements, questionnaire surveys and performance tests. The results reflected that under the condition of radian floor heating in winter, changes in thermal, visual and acoustic environments could have a significant influence on occupants’ satisfaction with the environment. However, the research performance was affected only by thermal and acoustic conditions. There was a weak correlation among thermal, visual, acoustic and indoor air quality comfort.

From worship space to auditorium: Acoustic design and experimental analysis of sound absorption systems for the new auditorium of San Francesco al Prato in Perugia (Italy)

In the present paper the design and the ante- and post-operam experimental analysis of the acoustic performance of the church of San Francesco al Prato in Perugia (Italy) are presented and discussed within the framework of a long process of design and construction. During its refurbishment (2012–2020) and its transformation from worship to auditorium, the authors carried out four experimental campaigns for the evaluation of the main acoustic indexes (Reverberation Time and Clarity Index). Measured data were used to validate four simulation models (one for each experimental campaign) by means of Ramsete software for the prediction of the acoustic behavior of the auditorium and for the design of the indoor finishes. A laboratory experimental campaign in a small-scaled reverberation room was carried out for the characterization and the design of the sound absorptive canopies hanged over the ceiling, which represent the acoustic “dominant” layer, especially at medium frequencies, where the room needed the most significant correction. A total number of 20 canopies (perforated resonant systems with rock wool inside) were installed, for a total surface area of about 180 m2; together with the plaster and the 514 armchairs, they played an important role in reducing the Reverberation Time.The acoustic quality indexes gradually approached to their optimal values for music listening during the works period: the average Reverberation Time passes from a value of 4.56 s ante-operam to a value of 1.96 s post-operam; C80 passes from a mean value of −4 dB to about −0.5 dB. The first values are in line with the ones of other churches with the same volume found in the Literature, whereas the second ones are within the optimal ranges for music listening.

Evaluation of the main sensitivity drivers in relation to indoor comfort for individuals with autism spectrum disorder. Part 2: Influence of age, co-morbidities, gender and type of respondent on the stress caused by specific environmental stimuli

Variations of environmental parameters, like thermo-hygrometric, acoustic, visual and indoor air quality can influence the sensitivities of individuals on the spectrum. This paper presents research on this issue, studied by means of questionnaires administered to parents and professional caregivers taking care of people with Autism Spectrum Disorder (ASD).The study highlights that there are clear differences if the indirect evaluations are performed by parents or professional caregivers, in relation to the specific identification of stress sources. Additionally, acoustic domain is identified as the one causing the major stress, especially caused by strong noises and particular sounds such as voices, animal sounds and impacts, and its dependence on the severity of autism is evidenced. Furthermore, a lower impact of thermal, visual and IAQ factors is determined, with the exception of some specific stimuli like light contrast (glare), high illumination, particular light sources or stale air. Finally, this paper provides evidence of the influence of age, severity of autism and co-morbidities on perceived stress.