Sound System Research Articles

Introduction of a free sound system design exchange format (SDE) for data from different sound systems for noise predictions with complex summation

To consider the correlated sources of sound systems from different manufacturers in noise predictions equally with complex summation, a free exchange format for sound system planning software on the one hand and environmental noise software on the other is being defined in a cooperation with d&b audiotechnik, L-Acoustics and SoundPLAN: SDE = Sound/System Design/Data Exchange/Export This paper introduces the SDE format, its motivation and structure. With increasing open-air events in urban areas, potential problems with noise also increase. Proactive noise predictions can help prevent noise from becoming a problem in the first place. Until now it has not been possible to use data from planned sound systems from different manufacturers for equivalent calculations with complex summation. Modern sound systems have high directivity, especially loudspeaker arrays. The directivity of arrays results from superposition of sound waves from all loudspeakers. This effect is used specifically with line arrays and subwoofer arrays to optimize sound and coverage in audience areas. However, the resulting emission of an entire sound system is not constant over distance. Time-of-flight and relative phase at the receiver points must be considered with complex summation.

On the acceptance limits for short-term level fluctuation of sound calibrators

To ensure noise measurement accuracy, sound calibrators are used to check the sound level meter accuracy before and after any such measurements, as required by most noise regulations. The sound calibrator itself needs to be calibrated routinely and traceable to national standards. The International Standard IEC 60942, Electroacoustics - Sound calibrators, specifies performance requirements for the sound pressure level, short-term level fluctuation, frequency, and distortion and associated test methods. However, the acceptance limits for short-term level fluctuation specified in IEC 60942 is problematic. The short-term level fluctuation acceptance limits specified in Table 2 of IEC 60942 for the level variations inherited by a stable sinusoid at low frequencies are either underestimated or overestimated. In this paper, a detailed theoretical analysis is presented addressing this particular issue. Closed-form solutions are obtained for typical sinusoidal sound signals. Two experimental setups and measurement results for the validation of the theoretical analysis are also presented. One uses a commercial sound level meter and the other uses a precision sound pressure measurement system developed recently at the National Research Council Canada. A revised table for the acceptance limits is then proposed for the future revision of Table 2 of IEC 60942.

Applicability of the theoretical formulations of C50 and U50 for predicting speech intelligibility in lecture halls

Theoretical formulations of the clarity C50 and the useful-to-detrimental ratio U50 for speech intelligibility have been derived under the assumption of diffuse sound field, which could be useful for room acoustic design. However, their applicability to a variety of daily rooms is still unclear. In this study, room impulse responses are measured in several lecture halls of various sizes with and without a sound reinforcement system, and the distributions of C50 and STI are obtained in each lecture hall. Then the theoretical values of C50 and U50 with and without Barron's revision are compared with the measured values, considering a level of HVAC background noise. Additionally, the relationship between the measured STI and C50 or U50 is examined, and the proportion of seats in each grade of speech intelligibility is evaluated in each lecture hall.

Development of an experimental technique for measuring polar diagrams of adaptive directivity implemented in hearing aids

Nowadays, hearing aids have efficient signal processing options to improve speech intelligibility in noise. This work concerns the characterization of the microphone systems directivity available in hearing aids. In recent decades, "adaptive" directivities have been implemented in hearing aids, thus making it possible to focus on useful sound sources in the hearing aid patient environment. These options use the principles of sound environments detection, acoustic beamforming and noise reduction. Performances of these options can be estimated with subjective methods (as speech audiometry in noise), and objective methods (listening effort, intelligibility indicators as HASPI, SII, STI, etc.). But these methods provide an overall assessment of all the processing involved in speech enhancement and are not designed to characterize the effects of adaptive directivity. We developed an experimental technique based on sound sources separation with phase opposition diffusion (known as "Hagerman" method) to draw polar diagrams of adaptive directivity, for realistic sound environments. We used a sound multi-diffusion system to generate various sound environments with noise and speech sources around an artificial head equipped with hearing aids. The first results show the adaptive directivity effects associated with noise reduction provided by the latest hearing aids generation on everyday hearing scenes.

Can sound field amplification be of use in daycare centres? An explorative pilot study

This study evaluates the effects of Sound Amplification Systems (SFA) on reducing vocal strain in daycare staff and enhancing children's concentration in noisy environments. Utilizing a mixed-methods approach, structured questionnaires were distributed to 11 daycare staff members in Turku, Finland, to gather both quantitative and qualitative data on their experiences with SFA. The analysis revealed that SFA significantly lowered vocal strain for staff, especially during group activities, and improved children's engagement by making speech more intelligible amidst background noise. However, practical challenges such as SFA mobility and adaptability in diverse settings were identified. The findings suggest SFA's potential benefits in early childhood educational settings, while also highlighting the need for further research to address implementation challenges and confirm these preliminary results with a larger participant sample.

Annoyance assessment of the combined effect of railway noise and vibration including physiological measurements

The prediction of annoyance due to railway transportation in residential areas is crucial to correctly dimension noise and vibration reduction solutions. In situ annoyance assessment for multiple exposition scenarios requires to convince many residents to take annoyance tests combined with noise and vibration measurements inside their homes. Such approach is not adapted to large-scale experiments. Therefore, the VibAcouPhysio project aims at studying annoyance due to railway noise and vibration in laboratory conditions. A vibrating platform combined with a high-quality sound reproduction system has been designed for this project to reproduce the noise and vibrations of a train pass-by. Annoyance is estimated by multiple means including questionnaires, cognitive tasks performance assessment and various physiological measurements. Twenty participants were exposed to various train pass-by signals as if they were seating at a table inside their housing. The results show a significant correlation between physiological metrics, the annoyance evaluated in the questionnaires and the physical indicators derived from the noise and vibration signals. The main purpose of the VibAcouPhysio project is to rank various physical indicators describing noise and vibration signals according to their correlation to the perceived or measured annoyance.

Designing a practical physical framework for AI-enhanced sound detection and localization in vehicles

This paper presents the practical framework of an AI-implemented system currently in development for the detection and localization of external sound events to the vehicle. We delve into the initial block of the automotive project, analyzing sounds of interest and the noise we encounter, addressing the strategic arrangement of the four microphones on the sides of the vehicle, conceived as the sound input system. This configuration not only optimizes signal capture but also acts as sensitive ears, allowing the system to effectively analyze the acoustic environment. To mitigate wind interference, we have designed a microphone placement system that considers the vehicle's aerodynamics. The strategic location and implementation of aerodynamic protectors significantly minimize the impact of wind on the microphones, ensuring a sharper capture of acoustic signals. Complementing this arrangement, we apply advanced noise elimination processes, further enhancing the quality of the captured signals. Although in its early stages, this project aspires to provide effective solutions for vehicular acoustic perception, marking the beginning of a journey towards innovation in the detection and localization of sounds in mobile environments.

Sonagining the workspace : a user-centric workshop

The Laboratoire d'Expériences du Bureau (LEB) is designed as an experimental, educational and experiential space for workspace designers. Its purpose is to provide a better understanding of the implications of design choices on the likely sound experience of people at work. Equipped with a set of mobile acoustic devices, an sound ambience generator software and a multi-channel sound system, it reproduces a range of sound phenomena and immerses listeners in a range of sound ambiences in a work situation. Users are helped to gradually become aware, through sound experience, of the implications of their design choices. The process is part of a research approach to the design of sound devices based on the ideation of new paradigms and the modeling of hypothesis. This article intends to present the key concepts of the project, how it differs from other comparable approaches, its state of progress as well as the limits and difficulties encountered.

Feedback on the creation of a scientific show using immersive sound

This presentation is devoted to feedback on the creation of a scientific show produced in collaboration between two acoustic laboratories, musicians and a loudspeaker manufacturer. The aim of the show is to simply explain sound perception to a wide audience using an immersive sound system. The presentation focuses on the creative process (including scenario writing, musical compositions, choice of technical solutions for the audio rendering) and the compromises made between scientific rigor and the artistic aspect. The various phases of the work carried out over almost two years are explained in order to formalize the creative process and the need to find a specific method that is suitable for both artists and scientists.

Towards achieving inclusive energy in SSA: The role of financial inclusion and governance quality

Energy poverty is a serious impediment to achieving Sustainable Development Goal 7 (SDG-7), thereby compelling policymakers and the scientific community to make collaborative commitments to address energy issues worldwide. While there is growing debate on the prevalent determinants of energy poverty, the empirical scrutiny of the contributing role of financial inclusion and governance quality remains elusive in existing literature. Therefore, this study investigates the impact of financial inclusion and governance quality on energy poverty in 29 sub-Saharan Africa (SSA) spanning 2004–2022. The empirical analysis was accomplished using the Augmented Mean Group (AMG) and Common Correlated Effects Mean Group (CCEMG) techniques with the Driscoll-Kraay standard error (DKSE) approach as a robustness check. The empirical outcomes indicate that a well-developed financial system that fosters easy and quick access to credit, especially among marginalized households, leads to the affordability of modern energy resources, thereby ameliorating energy poverty in the region. Additionally, the findings demonstrate the undeniable role of good governance in fostering a sound and inclusive financial system that enables households to access energy resources, ultimately reducing energy poverty in the region. Based on these outcomes, this study proposes important policy insights for the design and implementation of inclusive financial and energy policies.

Singapore’s Core Competencies And Key Success Factors That Led To Sustainability Of Growth And Development

In the last few-decades the world has witnessed an unprecedented increased economic development of the Singapore. The rapid development from a low-income economy to a well developed country is driven and facilitated by radical changes in Information and communication technology, sound educational system and encouraged research and innovation-intensive industry. Conclusively, a strategic location, good governance and excess foreign economic engagements helped transformed the country’s economy

Implementation of Active Noise Canceling for Noise Reduction using Embedded System

Abstract This paper presents the utilization of active noise canceling (ANC) technology using an embedded system for a sound insulation box. The ANC system for the insulation box is designed to replace conventional heavyweight passive sound absorber systems. A feedback filtered-x least mean square (FxLMS) algorithm is utilized to create the opposing-noise signal to counteract the incoming noise entering the box, so that reducing the noise level inside the box. In our previous work, we delved into a similar topic of using ANC for a sound insulation box, but the prior system had limited performance due to its inability to operate in real time. In this study, the FxLMS algorithm is implemented on an ARM Cortex-based microcontroller development board. A feedback structure is utilized, with an error microphone positioned in the middle of the box The ANC system’s capability was evaluated for pure tone noise in the frequency range of 63 Hz to 630 Hz. The experimental findings indicate that the ANC system has the capability to cut back the noise level up to 4 dB for some frequencies.

A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

Implementasi Pendekatan Komunikatif (Communication Approach) Dalam Meningkatkan Keterampilan Berbahasa Arab

<p><strong><em>Abstract</em></strong></p><p><em>The approach can be interpreted in English is (approach), which is a statement of establishment, philosophy and belief. Communicative means being able to convey messages well. The communicative approach is a language learning approach that emphasizes the mastery of language skills than language structure Language is a means of communication with each other, so that if someone does communication interaction, of course, must understand each other the object being discussed so that the goals to be achieved will be more directed towards their goals. However, if the interaction is not communicative because it does not understand what is being discussed because it does not understand the language used, causing the expected goals will not be achieved. Language is considered as a skill, not science, so language skills should be able to include four things, namely listening, speaking, reading, and writing. And one of the characteristics of these skills is to be done by continuous training. If one of the methods used previously is a direct method (direct method), then this method is updated so that it becomes an audiolingual method</em><em>.</em><em> The writing of this article aims to describe the application of a communicative approach through various learning methods in Arabic learning to increase language disappearances. The method used is the library research method originating from various library sources. The results of this writing indicate that methods that emphasize more to listening and speaking skills.</em><em> Speaking skills are one type of language ability to be achieved in teaching Arabic. And in essence is a meter of reproducing the flow of the sound system of articulation to convey the will, the needs of feelings, and desires to others. Exercise in Arabic language so that students are able to communicate well and correctly with others. Starting the practice of speaking is based on the ability to listen, the ability to mastery vocabulary and courage to reveal what is in his mind.</em></p>

Twisted industrial structure, land financing mode and social security

This paper explains the disparities in the level of social security across different regions in China from the perspective of industrial structure distortions and discusses the moderating effect of land financing models. The results show that industrial structure distortions have a significant negative impact on social security expenditures; the lower the intensity of land investment, and the higher the intensity of land finance and land-based finance, the stronger the negative impact of industrial structure distortions on social security expenditures. The research conclusion of this paper has the reference significance for the government's sound and sustainable multi-level social security system.

Coaxial tribonegative yarn TENG with aromatic polyimide as charge entrapment layer for real-time edge ball assessment in cricket sports

Energy harvesting yarns working on triboelectric effect by converting mechanical energy into electricity for running wearable electronics as well as operating as self-powered sensors, are superb choices for wearable electronics of current and future generations. However, current yarn-based triboelectric nanogenerators (TENGs) designed through electrospinning process are limited in achieving higher outputs, comfort, mechanical strength, washability, and industrial scalability. In this study, we introduce a flexible and durable tribonegative yarn TENG (TNY) with an electrospun polyimide (PI) intermediate charge trapping layer between the electrode and electrospun superhydrophobic polyvinylidene difluoride (PVDF)/Poly(dimethylsiloxane) (PDMS). In this coaxial arrangement, the PI charge entrapment layer enabled the TNY to exhibit an output voltage of 14 V in a 2.5 cm length, compared to only 8 V for TNY without PI layer. The TNY can be successfully woven and knitted into electronic textiles (E-Textiles), with their outputs compared based on various knitted and woven patterns. The E-Textile maintained considerable outputs after washing and withstood 5000 Martindale abrasion cycles. The superhydrophobic behavior also enabled TNY to harvest water energy from a running tap. We demonstrated the potential of these E-Textiles for edge ball sensing in cricket sports in real-time by leveraging the benefits of triboelectrification, thereby avoiding the need for complex camera setups and sound systems for judging ball movements at ± 140 km/hr in real sports. We also employed E-Textiles for smart switch functions, which can be beneficial in smart systems. This study demonstrates the improved performance of yarn-based TENGs and further extends the applications of TENGs in sports analysis. It provides a facile and high-efficiency approach for designing triboelectric sensors, offering a cost-effective alternative to complex and expensive sports equipment.

Tailored for vehicle horn: A novel sound source capture method

The development of a horn sound capture system, capable of replacing manual control, offers a promising solution for alleviating horn noise. Existing horn sound systems lack localization algorithms that are capable of robustly resisting interference. To address this issue, this paper introduces an innovative horn sound capture system, including hardware and algorithms for sound recognition and localization. The pivotal innovation of the system is the introduction of the Sub-SRP algorithm, an advancement of the steered-response power phase transform (SRP-PHAT). Leveraging the frequency characteristics of horn sounds, it employs a series of filtering and spectral subtraction techniques to effectively filter out non-horn noise sources. In the interference experiment and field test, the Sub-SRP algorithm achieved DOA scores of 0.96 and 0.95, respectively, showing an approximately 10% improvement compared to the existing weighted SRP-PHAT, this improvement is even more pronounced under strong interference, increasing to 17%. This improvement significantly enhances the system’s ability to accurately capture honking vehicles and resist interference. Additionally, the horn sound recognition algorithm achieved accuracy rates of 95.75% and 97.65% in the two experiments, demonstrating the system’s effectiveness. In summary, this study contributes to the advancement of urban noise management and intelligent noise control systems.

The role of sound-to-symbol literacy in phonological awareness: Evidence from Cantonese

Phonological awareness reflects linguistic knowledge related to the sound system of a language. Individual development of phonological awareness is known to progress from larger to smaller sized units and is promoted by the acquisition of literacy, especially in alphabet-based writing systems that are built around sound-to-symbol correspondences. The present study addressed the nature of phonological awareness in speakers of a logographically scripted language. It investigated phonological awareness in adult speakers of Cantonese hailing from Hong Kong who (compared to speakers of other logographically scripted languages) traditionally received little sound-based assistance from tools like Pinyin or Zhu-yin-Fu-Hao when they acquired orthography. The study adopted an individual difference approach, quantifying individually variable levels of experience with a sound-to-symbol writing system and their relationship to phonological awareness. Fifty-seven Hong-Kong speakers of Cantonese took part online, completing rhyme judgment and phoneme monitoring tasks, alongside an extensive background questionnaire. The main prediction that Cantonese speakers who had a relatively high level of experience with sound-to-symbol writing would show an advantage in phonological awareness at the subsyllabic level was largely borne out by the data. The findings of the present study suggest that phonological awareness is a complex set of dissociable skills, shaped by the linguistic and orthographic experience of individual speakers.

Analysis of concrete damage at anchorage end of the high-speed railway bridge sound barrier under the 400 km/h train-induced wind loads

The sound barrier installed on high-speed railway bridges withstands repeated train-induced wind load, which may lead to concrete damage at its anchorage end. This paper focuses on the assessment of concrete static damage at the sound barrier anchorage end under train-induced wind loads. The nonlinear finite element model of the sound barrier anchorage system is established to analyze the stress distribution, strain distribution and static damage of concrete structure at the anchorage end under 400 km/h train-induced wind loads in respect of different bolt preloads. The simulated results illustrate that both mortar and concrete near bolt holes suffer a certain degree of tensile and compressive damage. The maximum tensile and compressive damage factor values for mortar and concrete are 0.930, 0.643 and 0.892, 0.434 respectively. In addition, the effects of train-induced wind load on the internal force of the sound barrier anchorage take nearly no account, with a maximum of only 0.68 %. The results indicate that bolt preload is the most significant factor for concrete static damage, while the train-induced wind load appears negligible. An appropriate bolt preload can avoid the concrete static damage of the sound barrier anchorage end, and guarantee the structural stability of the sound barrier.

An experimental study of acoustic bird repellents for reducing bird encroachment in pear orchards.

Bird invasion will reduce the yield of high-value crops, which threatens the healthy development of agricultural economy. Sonic bird repellent has the advantages of large range, no time and geographical restrictions, and low cost, which has attracted people's attention in the field of agriculture. At present, there are few studies on the application of sonic bird repellents in pear orchards to minimize economic losses and prolong the adaptive capacity of birds. In this paper, a sound wave bird repellent system based on computer vision is designed, which combines deep learning target recognition technology to accurately identify birds and drive them away. The neural network model that can recognize birds is first trained and deployed to the server. Live video is captured by an installed webcam, and the sonic bird repellent is powered by an ESP-8266 relay switch. In a pear orchard, two experimental areas were divided into two experimental areas to test the designed sonic bird repellent device, and the number of bad fruits pecked by birds was used as an indicator to evaluate the bird repelling effect. The results showed that the pear pecked fruit rate was 6.03% in the pear orchard area that used the acoustic bird repeller based on computer recognition, 7.29% in the pear orchard area of the control group that used the acoustic bird repeller with continuous operation, and 13.07% in the pear orchard area that did not use any bird repellent device. While acoustic bird repellers based on computer vision can be more effective at repelling birds, they can be used in combination with methods such as fruit bags to reduce the economic damage caused by birds.