Sound Device Research Articles

Characteristics of Evacuation Guidance Sounds for the Visually-Impaired during Fire Alarms

Recently, various intelligent evacuation guidance systems that can be applied in buildings were studied. Technology development for the evacuation of vulnerable people such as the visually-impaired is necessary. Voice guidance is a method used to lead the visually-impaired toward the evacuation route. However, it is necessary to review whether it is possible to hear and understand the voice guidance during the sounding of fire alarms. In this study, simulations were conducted to predict the sound power level of the voice guidance device that can secure an acceptable sound transmission index of the guide sound and the appropriate distance from the voice guidance device, when a fire alarm sound is generated in a hallway space. The study found that an acceptable sound transmission index was achieved when the sound power level was 100 dB and the appropriate type of sound device was found to be a necklace-type headset or a regular headphone.

Cultural Heritage of Turkic-Speaking Peoples in World Collections: Historical Audio Recordings of The Berlin Phonogram Archive

In the countries of the Turkic world, for more than 100 years of using sound recording devices, a huge amount of various sound materials on the traditional musical art of the Turkic peoples have been accumulated, recorded by scientists from different countries, in different regions and on different media. The first historical sound recordings of the Turkic-speaking peoples, which are of significant historical, cultural and scientific value, are kept separately in various foreign archives and have not received a complete and comprehensive study. This article provides a brief presentation of the unique historical audio materials of the music of the Turkic-speaking peoples, which were collected by German scholars at the beginning of the 20th century and are stored in the Berlin Phonogram Archive.

Poetycki model prozy Iwana Ptasznikaua (na przykładzie opowieści Łonwa)

This article is devoted to an issue of the poetry of Ivan Ptasznikau’s prose that is illustrated on the example of one of the most significant texts written by this Belarusian author titled Łonwa (1964). The novel is built around historical issues (events from The Second World War and its consequences) and makes a perfect example of a conscious creation of a narrative language, dialogues and characters’ monologues on a strategy basis and techniques typical of poetic texts. It is proved not only by countless metaphors and comparisons, behind which the author was hiding a painful wartime reality but also by excellent syntax organisation that brings out new semantic spaces of the piece. Ivan Ptasznikau mixes various types of repetition (anaphors, epiphors and concatenations) within relatively short sections in an incredibly skillful way and uses sound values from the repetitiveness of letters and syllables (their multiplications or prolongations), thanks to which he creates a very suggestive space, saturated with colours, sounds and smells that are used not necessarily as a background for characters or events but as a means to shape senses and meanings that emerge from the plot. What is particularly interesting is the fact that he combines a narrative level with a feature level by using sound and rhetorical devices and a peculiar linguistic and stylistic over–organization. Particular words, recurring phrases and systematically recurring strategies and syntax tricks (especially those that form the so–called poetry of atmosphere) bond these two levels together, broadening the interpretation field of the whole piece.

Gamma frequency sensory stimulation prevents brain atrophy, improves sleep and memory in probable mild Alzheimer’s patients

AbstractBackgroundNon‐invasive gamma frequency light and sound stimulation at 40Hz reduced Alzheimer’s disease (AD) pathology and improved performance during behavioral testing in mouse models of AD (Iaccarino et al., Nature, 2016; Martorell et al., Cell, 2019; Adaikkan et al., Neuron, 2019). Sensory stimulation inducing 40Hz entrainment reduced amyloid and hyperphosphorylated tau burden and prevented brain atrophy in different mouse models of AD. Performance on tasks testing short‐term memory and spatial learning improved after 6 weeks of daily 40Hz stimulation. We therefore hypothesized that translation of gamma entrainment with light and sound can be used as a disease‐modifying therapeutic for AD.MethodsWe conducted a placebo‐controlled, randomized control trial (n = 15) in volunteers with probable mild AD to use our light and sound device at home for one hour daily (NCT 04042922). Control devices delivered constant light and white noise while devices with the active setting produced patterned and synchronized light and sound at 40Hz. Electroencephalogram (EEG) was used to evaluate for safety and entrainment when using the 40Hz stimulation. Weekly phone questionnaires were used to assess safety. Magnetic resonance imaging was used to evaluate brain structure and actigraphy was used to record sleep. Face‐name association delayed recall was done to assess changes in cognition.ResultsWe report interim results after 3 months of daily 40Hz stimulation. Mild AD patients were highly compliant with usage in both the control and active groups. EEG data show that our novel light and sound device safely and effectively induced 40Hz entrainment in subjects with mild AD. After 3 months of daily stimulation, 40Hz entrainment prevents both hippocampal atrophy and ventricular enlargement and the extent of ventricular change differs between groups (p = 0.034, p = 0.024, p = 0.043, respectively). Circadian rhythmicity also improved with 40Hz stimulation (p = 0.03). Performance on the face‐name association delayed recall test improved in accuracy (p = 0.004).ConclusionsGamma frequency light and sound stimulation can be used safely daily for 3 months and prevents AD‐related degeneration. Induced entrainment using sensory stimulation at 40Hz shows promise as a novel disease modifying therapeutic for Alzheimer’s dementia.

MPEG-H Audio System for SBTVD TV 3.0 Call for Proposals

Under the name “TV 3.0 Project”, the Brazilian Terrestrial Television System Forum (SBTVD) has issued the Call for Proposals (CfP) for a next generation Brazilian digital TV system, in July 2020. The MPEG-H Audio system, based on the open international standard ISO/IEC 23008-3, has been proposed by Fraunhofer IIS, ATEME, the Digital Broadcasting Experts Group (DiBEG) and the Advanced Television Systems Committee (ATSC). This paper provides an overview of the MPEG-H Audio system and the TV 3.0 Project requirements for the audio component. The TV 3.0 Project specifies a detailed test and evaluation procedure for verifying the fulfillment of the requirements. With wide industry support, the MPEG-H Audio system brings immersive sound, advanced interactivity, and accessibility options, as well as advanced features like hybrid delivery, consistent loudness after user interaction, connectivity options for external sound devices and seamless configuration changes. The MPEG-H Audio proponents have submitted a complete production and broadcast real-time chain to the SBTVD Forum which demonstrates the most advanced features.

Objective Assessment of Covid-19 Severity Affecting the Vocal and Respiratory System Using a Wearable, Autonomous Sound Collar.

IntroductionSince the outbreak began in January 2020, Covid-19 has affected more than 161 million people worldwide and resulted in about 3.3 million deaths. Despite efforts to detect human infection with the virus as early as possible, the confirmatory test still requires the analysis of sputum or blood with estimated results available within approximately 30 minutes; this may potentially be followed by clinical referral if the patient shows signs of aggravated pneumonia. This work aims to implement a soft collar as a sound device dedicated to the objective evaluation of the pathophysiological state resulting from dysphonia of laryngeal origin or respiratory failure of inflammatory origin, in particular caused by Covid-19.MethodsIn this study, we exploit the vibrations of waves generated by the vocal and respiratory system of 30 people. A biocompatible acoustic sensor embedded in a soft collar around the neck collects these waves. The collar is also equipped with thermal sensors and a cross-data analysis module in both the temporal and frequency domains (STFT). The optimal coupling conditions and the electrical and dimensional characteristics of the sensors were defined based on a mathematical approach using a matrix formalism.ResultsThe characteristics of the signals in the time domain combined with the quantities obtained from the STFT offer multidimensional information and a decision support tool for determining a pathophysiological state representative of the symptoms explored. The device, tested on 30 people, was able to differentiate patients with mild symptoms from those who had developed acute signs of respiratory failure on a severity scale of 1 to 10.ConclusionWith the health constraints imposed by the effects of Covid-19, the heavy organization to be implemented resulting from the flow of diagnostics, tests and clinical management, it was urgent to develop innovative and safe biomedical technologies. This passive listening technique will contribute to the non-invasive assessment and dynamic observation of lesions. Moreover, it merits further examination to provide support for medical operators to improve clinical management.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12195-021-00712-w.

New high fidelity (hi-fi) three-dimensional thermophone CNT sponge

A novel, high-fidelity (hi-fi) thermophone based on three-dimensional porous CNT sponge is designed for attachable and wearable sound generation devices. In addition to its simple structure and easy fabrication, CNT sponge thermophone exhibits excellent thermoacoustic and mechanical characteristics, particularly its wideband frequency response, due to its highly efficient energy conversion capability through the CNT nano-structural materials. In this paper, the hi-fi sound response of suspended CNT sponge thermophones is analyzed by theory and experiment. A theoretical thermoacoustic model for CNT sponge thermophone is proposed and the corresponding analytical solutions are established. To explore applications of CNT sponges, a flexible thermophone and a hi-fi thermoacoustic loudspeaker are developed and investigated by experiment. The flexible CNT sponge thermophone presents stable sound response before and after it is attached to some complicated surfaces. The CNT sponge thermoacoustic loudspeaker shows a wide bandwidth, high-quality audio output, and stable sound response. Such premium characteristics ensure its feasibility as a potential replacement for the conventional voice coil and piezoelectric loudspeakers.

His Master’s Voice: Sound Devices in Bram Stoker’s Dracula

One year after the publication of Dracula (1897), the English photographer Francis Barraud was commissioned a painting from his picture of a dog looking at and listening to a cylinder phonograph. His work, entitled His Master’s Voice, became one of the most famous logos in the world. Barraud’s painting was particularly meaningful for not only did it raise the issue of the amplified voice, but it also visualized the impact and effect that technological instruments had on the amplified voice. The phonograph shows how voices can become disconnected from the material body and raises the issue of what actually constitutes a voice. Among the modern technological devices mentioned in Bram Stoker’s Dracula, the phonograph plays an important role, a presence which is both disconcerting and reassuring. The power and the uncanny effect of the disembodied voice is evident in Mina’s reaction to Dr Seward’s phonographic recording, a ‘wonderful’ and ‘cruel’ device as it records not only the speaker’s voice but also its tone, thus revealing bodily sounds which writing, instead, hides. In Dracula, the distinction between speech and writing is constantly under pressure: on the one hand, the characters’ urge to write (journals, letters, etc.), on the other there is an agency of oral interaction. From Renfield’s calling in of the vampire (a master who needs a servant to be welcomed in), to Dracula’s attempt at mastering oral English in order to conceal his foreignness, the novel proves to be an important example of how literature deals with sound devices.

Pseudospin-dependent Acoustic Topological Insulator by Sonic Crystals With Same Hexagonal Rods

We report the experimental and numerical realization of a pseudospin-dependent acoustic topological insulator based on two sonic crystals constructed by the same regular hexagonal rods. Based on the zone folding mechanism, we obtain double Dirac cones with a four-fold deterministic degeneracy in the sonic crystal, and realize a band inversion and topological phase transition by rotating the rods. We observe the topologically protected one-way sound propagation of pseudospin-dependent edge states in a designed topological insulator composed of two selected sonic crystals with different rotation angles of the rods. Furthermore, we experimentally demonstrate the robustness of topological sound propagation against two types of defects, in which the edge states are almost immune to backscattering, and remain pseudospin-dependent characteristics. Our work provides a diverse route for designing tunable topological functional sound devices.

Design of a Long-stroke Low-frequency Sound Device

In order to improve the radiation performance of low-frequency sound device, a design method for a long-stroke low-frequency sound device is proposed, which mainly involves the design of the drive structure and radiation structure and the drive structure is designed with an electric long stoke. The flat plate and conical structures of piston plate of radiation structure are compared, and a long-stroke radiation structure with a low-damping guide support motion pair uniformly distributed in the circumferential direction is proposed. The numerical simulation results show that, with six straight-line bearings circumferentially and uniformly distributed, the displacement and stress distribution of piston plate are better than those of piston plate with three straight-line bearings installed in the same manner. The sound device is further tested in the experiment, and it is found that the vibration displacement amplitude at the center of piston plate is 3.9 mm (20 Hz), and the maximum sound pressure level of 40 Hz is found at the location 10 m from the center of sound device along the axial direction, reaching 105.3 dB.

Ortam Gürültü Şiddetinin, Ios ve Android Tabanlı Ses Ölçüm Uygulamaları ile Ticari Ses Ölçüm Cihazları Kullanılarak Karşılaştırılması ve Ölçüm Belirsizliğinin Elde Edilmesi

In this study, sound measurement between ios and android operating system based mobile phones (Soundmeter, Decibel X) and commercial sound measurement devices (Cem dt8852, Svantek sv104) was tested. Sound measurement intensities and energies were determined, measurement uncertainties of ios and android devices according to the application were determined. Measurements were carried out at the same time in the indoor and outdoor environment. Iphone 7+ (Ios operation system) and Samsung note 8 (Andorid operation system) used. Significant sound measurement differences were obtained between the two different mobile phone applications. There was no significant difference between commercial measurement devices. Commercial measuring devices were calibrated and can be used as reference devices. Using these devices, it was observed that ios and android-based applications receive faulty measurements on average between 10-20%. As a result of the measurements taken with the applications, it was determined that the measurement uncertainty is in the range of approximately 4-5dB.

Band tuning and channel reconfiguration of sound waves in coding topological metamaterials

The adjustment of the working band of the acoustic metamaterials poses a great challenge, limiting their practical applications. Here, a 2-bit coding acoustic valley Hall topological insulator is reported based on the triangle-lattice scatterers. The former and latter bits are employed to control two diverse scatterers and channels, respectively. The gapless band and transmission channel of the topological edge mode can be adjusted under the control of the four different coding sequences and two other cases. In theory, we reveal the topological phase transition, illustrate the topological edge mode, and predict the working bands of the designed valley Hall topological insulator. Both the simulated sound pressure field patterns and experimented transmission spectra agree well with the predicted results, indicating the properties of band tuning and channel reconfiguration of the valley Hall topological insulator. Our design opens up new avenues for designing coding acoustic metamaterials, showing potential in the achievement of the intelligent, flexible, and programmable sound devices.

Game Effect Based on Particle System in Unity 3D

The gaming industry has been one of the main driving forces behind the development of advanced modern hardware such as multi-core, hyperthreaded processors, high-performance graphics processing units (GPUs), advanced sound processing devices, and extraordinary human-computer interface devices such as virtual reality helmets and brain sensor caps . The computer gaming industry has grown by leaps and bounds, becoming a mainstream software development sector, and earning billions of dollars in revenue each year. Computer games are like a book, a movie, or a museum .

Moving Cage: Vibration, Sonification and the Quanta of Time

Dear John is an experimental choreomusical work that reinterprets Cage's works while advancing his ideas of sound as sonic events and embodied choreography. In this episodic work, improvised movement unfolds to a soundscape of defamiliarized instruments, sound devices and sonicities of macro- and micro-movements. The correspondence and (in)congruence between dance movements and music's kinetic energy become the means to examine a politics of the body and sound, of music on movement. Additionally, in this ‘auditory architecture’ the quanta of time, its relations and (lack of) unity are exposed. This article then examines the intersubjective interplay of movement and music, body and sonicity; it considers the resonance of the performing body as intermaterial vibration and how this invites a sonic politics of relational possibility. The article will then also investigate the ways in which the interaction of motion and music, movement and stillness engenders experiences of time's indeterminacy and elasticity.

Optimization of Power and Torque with lower Exhaust Noise for FSAE Vehicle

The exhaust noise is considered to contribute disturbance to large extent in any vehicle. The sound wave cancellation device is used for better noise attenuation without much compromise on engine efficiency. This paper aims to design an advanced muffler which gives considerably lower back pressure in exhaust system line, thereby optimizing the power and torque of an engine. Study includes close monitoring of parameters such as power, torque, and transmission loss within the given boundary conditions. The limiting condition laid by Formula Society of Automotive Engineer (FSAE) is satisfied using Ricardo Wave Build software.

Textual Analysis of the Poem Sailing to Byzantium

This article attempts to accomplish a textual analysis of the poem Sailing to Byzantium composed by William Butler Yeats. The textual analysis incorporates the analysis of divergent aspects existed in a text. The crucial aspects are: the title of the poem, substance of the poem, form of the poem, tone of the speaker, sound devices, literary devices, diction, syntax, mode of expression, themes and so on. The article writer has tried to descry these aspects to analyze them in brief. This article, which involves the interpretation of the poem from the perspective of its texture, is significant to teachers and students who are engrossed in studying English poetry.

Topological refraction in dual-band valley sonic crystals

Valley pseudospins, as quantum states of energy extrema in momentum space, have been introduced from condensed-matter systems into classical sound systems, and several valley sonic crystals (VSCs) have been realized experimentally. However, in the existing VSCs, topological kink states generally appear in a single band gap, which apparently has become an obstacle for multiband topological sound devices. To overcome this challenge, we here experimentally demonstrate dual-band VSCs, in which robust valley kink states exist in two separated bulk band gaps. More interestingly, two opposite valleys separately located in two band gaps are locked to a single propagation direction, which arises from the fact that the bands below two band gaps show opposite valley Chern numbers at the K/K\ensuremath{'} valley. This double valley-locking phenomenon has been demonstrated via measuring the topological refraction of the kink states into the ambient space at a zigzag termination. We observe positive refraction at the lower band gap, whereas the coexistence of positive and negative refraction at the higher band gap. Additionally, we observe the robust valley transport through the sharp corners at two band gaps. The designed VSCs with the dual-band topological refraction and robust valley transport could find potential applications in multiband and multidirectional devices.

Impact of the COVID-19 Lockdown Measures on Noise Levels in Urban Areas-A Pre/during Comparison of Long-Term Sound Pressure Measurements in the Ruhr Area, Germany.

Background: A major source of noise pollution is traffic. In Germany, the SARS-CoV-2 lockdown caused a substantial decrease in mobility, possibly affecting noise levels. The aim is to analyze the effects of the lockdown measures on noise levels in the densely populated Ruhr Area. We focus on the analysis of noise levels before and during lockdown considering different land use types, weekdays, and time of day. Methods: We used data from 22 automatic sound devices of the SALVE (Acoustic Quality and Health in Urban Environments) project, running since 2019 in Bochum, Germany. We performed a pre/during lockdown comparison of A-weighted equivalent continuous sound pressure levels. The study period includes five weeks before and five weeks during the SARS-CoV-2 induced administrative lockdown measures starting on 16 March 2020. We stratified our data by land use category (LUC), days of the week, and daytime. Results: We observed highest noise levels pre-lockdown in the ‘main street’ and ‘commercial areas’ (68.4 ± 6.7 dB resp. 61.0 ± 8.0 dB), while in ‘urban forests’ they were lowest (50.9 ± 6.6 dB). A distinct mean overall noise reduction of 5.1 dB took place, with noise reductions occurring in each LUC. However, the magnitude of noise levels differed considerably between the categories. Weakest noise reductions were found in the ‘main street’ (3.9 dB), and strongest in the ‘urban forest’, ‘green space’, and ‘residential area’ (5.9 dB each). Conclusions: Our results are in line with studies from European cities. Strikingly, all studies report noise reductions of about 5 dB. Aiming at a transformation to a health-promoting urban mobility can be a promising approach to mitigating health risks of noise in cities. Overall, the experiences currently generated by the pandemic offer data for best practices and policies for the development of healthy urban transportation—the effects of a lower traffic and more tranquil world were experienced firsthand by people during this time.

Engineering acoustic reflections with programmable metasurfaces

Acoustic anomalous reflectors have recently drawn intense attention due to their ability to reflect impinging waves in non-specular directions. However, virtually all previously analyzed anomalous reflectors are passive structures with high spatial and/or temporal dispersion. Therefore, they are typically narrowband and unidirectional, namely they operate in the desired manner for only one direction of incidence. We discuss here a method to design quasi-omnidirectional and broadband anomalous metasurface reflectors composed of programmable non-resonant scatterers capable to manipulate the in-plane wave vector component in prescribed ways. We illustrate the method in 3D experiments in which the incident waves undergo negative reflections and show that the desired effect does not depend on the direction of incidence and has a bandwidth an order of magnitude larger than passive designs. Furthermore, we show experimentally that anomalous reflectors of various geometries can be realized by simply rearranging the active scatterers to fill-in the desired geometries as long as the periodicity of the scatterer lattice remains subwavelength. This is direct evidence that the presented metasurfaces behave like continuous materials rather than gratings or phonic crystal. The implications of this finding on the design of future sound manipulation devices will be discussed.

Sound wave balloon-assisted device implantation: a novel approach that merits consideration.

Sound wave balloon-assisted device implantation: a novel approach that merits consideration.