bluuebunny/crossref_metadata_2025 huggingface dataset:
Laser Doppler vibrometry measurement of the radiated sound power of a funicular floor system
Authors: Mendez Echenagucia Tomas , Roozen Bert , Block Philippe
Published: June 2017

Floor slabs represent a high percentage of the embedded energy in buildings. Lightweight floor systems, such as funicular shell structures, represent an important approach to the reduction of embedded energy in building by reducing material use in a significant way. As the amount of material is reduced, the sound insulation capabilities need to be studied in depth, particularly in the lower frequency range. The high stiffness of the shell structures has been shown with numerical experiments to have great potential for sound insulation in low frequencies. This paper presents laboratory measurements of the radiated sound power an unreinforced concrete funicular floor system in the low frequencies by means of laser Doppler vibrometry (LDV). The presented experiments use the velocities captured by the LDV system, coupled with the Rayleigh integral method to estimate the radiated sound power in an accurate way, without the known mode density problems present in low frequency microphone based measurements. A flat concrete slab of the same mass and dimensions is also tested for comparison. The paper presents the results of the two measurements and outlines guidelines for the acoustic optimization of the funicular floor system.
Perception of acoustic comfort in large halls covered by transparent structural skins
Authors: Rychtarikova Monika , Urban Daniel , Kassakova Magdalena , Maywald Carl , Glorieux Christ
Published: June 2017

Large halls, such as shopping malls, atria, or big entrance halls, often suffer from various acoustic discomfort issues, which are not necessarily caused by extremely high noise levels. Due to the large size of halls and consequently the long trajectories that sound waves travel between the source, interior surfaces, and the receiver, sound reflections arriving from surrounding surfaces are not as strong as they would be in smaller rooms. Reports in literature and comments by users of large halls concerning acoustic discomfort in large halls refer mainly to continuous reverberation related noise. Therefore, quantification of the acoustic comfort by the reverberation time, which is related to the average absorption of interior surfaces and by the equivalent sound pressure level, which in a large space is dominated by direct sound, is not adequate to describe the global acoustic comfort or soundscape. Based on statistical noise analysis on auralized soundscapes, this article proposes a set of measurable monaural and binaural acoustic parameters that adequately describes the acoustic comfort in large halls. The study is focusing on rooms covered by traditional materials, such as glass, plexiglass, etc., and ETFE (ethylene tetrafluoroethylene) foil structures.
Acoustical design of diffusers in concert halls using scale models
Authors: Jo HyunIn , Jang Hyung Suk , Jeon Jin Yong
Published: June 2017

A design process of diffusing surfaces has been verified by comparing with acoustic parameters in different scale models of a concert hall. A 1:50 scale model was used to determine locations of the diffusers as the main diffusing surfaces, and a 1:25 scale model was used to determine the structural height and density of the stage diffuser by examining the amount of diffusion on the stage. In addition, a 1:10 scale model was used to design the exact shapes of the diffusers by measuring the scattering and diffusion coefficients of them. The diffusers were installed on the concert hall stage and sidewalls of the auditorium; acoustic parameters, such as EDT, G, C80, and Np were measured to examine the amount of diffusion in the hall. As a result, the relative standard deviations of the parameters RT, EDT, and G decreased, whereas Np values increased. In the case of Np, the change was consistent with the variation of the diffusion amount. In conclusion, when designing a diffusing surface in a concert hall, the scale-model measurement is essential to determine the location and amount of the effective diffuser, as well as the direction of the diffuser geometry.
How (and why) does every Concert Hall “wake up” differently?
Authors: Kahle Eckhard , Green Evan , Knauber Fabian , Wulfrank Thomas , Jurkiewicz Yann
Published: June 2017

Masking is a loudness-dependent, non-linear process. Conversely, the process of unmasking is significant when considering the perceptual effects of music dynamics: the audibility of reflections relative to the direct sound is loudness-dependent, as shown by Wettschurek in the 1970s. To summarize his description of an orchestral crescendo: in pianissimo , all sources are clearly localized and the auditory image is fully frontal; then, as loudness increases, the room increasingly wakes up as reflections progressively become unmasked; and, finally, in full forte , the room is present, and ideally, the listener should be enveloped by sound. Wettschurek’s description implies a linear increase in spatial impression with loudness; however, the effect of musical dynamics is different in every hall, determined by the unique reflection sequence at a particular listening position. As a consequence, different rooms can lose clarity at different loudness levels, not necessarily only during saturation at fortissimo. Recent research by Lokki indicates that the signature of a room is determined by the details of the early room response. The links between the signature of a room and the unmasking of reflections will be discussed.
Links between spatial impulse response and binaural dynamic responsiveness in concert halls
Authors: Essert Robert
Published: June 2017

Recent research at Aalto University suggests that binaural dynamic responsiveness (BDR) in concert halls is (a) desirable and (b) a result of interaction between the emphasis of higher overtones at stronger dynamic levels and the early response of the room; also that tall, narrow, parallel sided “shoebox” halls have a greater degree of BDR than wider non-shoebox geometries. We have been analyzing the time evolution of spatial impulse responses and their connection to room geometry. In a recent paper, we looked at how wall tilt affects the growth of lateral energy in the room. In this paper, we consider how the shape of forward integrated lateral energy in a spatial impulse response may affect perceived strength, spaciousness, and binaural dynamic responsiveness.
Towards a common parameter characterizing the dynamical responsiveness of a concert hall
Authors: Lokki Tapio , Pätynen Jukka
Published: June 2017

Dynamic responsiveness is an important feature in room acoustics for making music more enjoyable. The concert hall should render the most silent pianissimos audible everywhere, including the last row, yet support fully the loudest fortissimos. The realization of these effects is impossible to objectively quantify by analyzing solely the measured impulse responses. Therefore, the analysis should be coupled with additional information related to music and dynamics. These factors can include directivities of both sources and listeners, and the spectral changes in the source signals and hearing sensitivity according to the sound level. With such effects combined to the information obtained from the conventional impulse response, the dynamic responsiveness could be objectively measured. This paper presents a proposed analysis method which is then applied to a variety of measured concert halls. In addition, the results show what magnitude of differences in dynamic responsiveness could be found between concert halls.
Effect of concert hall acoustics on tonal consonance of orchestra sound
Authors: Pätynen Jukka
Published: June 2017

The sound of pitched orchestral instruments consists of harmonic frequencies which, in performances, are transmitted over room acoustics. The amplitude relations of the harmonic peaks affect the timbre of one tone. When two or more notes are played together, the effect of consonance and dissonance becomes prominent. The degree of consonance for intervals of musical pitches have been explained by the frequency separation of their harmonic components in relation to the width of critical bands in human hearing. When the playing dynamics is varied, the changes in the instruments’ spectral envelopes are foreseen to alter also the consonance of simultaneous notes. Furthermore, the room acoustics influence the overall harmonic spectra conveyed to the listeners. This paper presents experiments on the tonal consonance of orchestra instruments at contrasting dynamic levels in various concert halls. By combining binaural hall measurements and anechoic instrument recordings with a consonance-estimating model, the following hypothesis is investigated: do the acoustics of concert halls change the orchestra sound’s consonance in different music dynamics?
Advances in adjustable acoustics systems in large multi-use performing arts centers in the U.S
Authors: Holden Mark , Nichols Mathew , Rivera Carlos
Published: June 2017

In the fall of 2016, Jaffe Holden opened three large (1800-2500 seats) multi-use halls with excellent acoustic reviews for all performances from symphony performances to highly amplified popular music. New designs of halls in Salt Lake City, Little Rock, and South Texas prove that this uniquely American building type has dispelled the myth that multi-purpose is in fact “no purpose.” Acoustic modeling calculations will be compared and contrasted with completed building measurements of EDT, RT30. C80, BR, and other criteria proving that these halls are excellent quantitatively and qualitatively.
Acoustic comfort for hypermarket cashiers: Problems and solutions
Authors: Martellotta Francesco , Della Crociata Sabrina , Simone Antonio , D'Alba Michele
Published: June 2017

An acoustic investigation carried out in a large hypermarket pointed out that several acoustic “zones” could be identified. Among them, the most critical was the checkout area, where cashiers were exposed to many noise sources like customers passing with shopping trolleys, “beeps” due to barcode readers, people voices, packaging and paging messages, and, above all, background music. In fact, as the checkout position usually divides the hypermarket from the shopping arcade, workers in this area are further exposed to music (and noise) from the nearby cafes, restaurants, and stores. As a result background noise LA90 is about 66 dB, with peaks (LA10) of about 72 dB. Subjective analysis also reported the highest rate of complaints in this area. Starting from a detailed analysis of the different noise sources and of the room acoustic conditions of the area (including reverberation time and speech transmission index measurements), a set of mitigation actions is analyzed and discussed.
Advances in room acoustics design for educational audio studios
Authors: Storyk John
Published: June 2017

Improved behavior, comfort, and performance are critical in creating today’s audio recording and post production educational facilities. As these facilities continue to grow and become more widespread in high school and secondary learning institutions, the challenges that they present also continue to grow. Fundamental acoustic behavior remains paramount, but unique considerations associated with the teaching aspect of these rooms present some interesting issues. These include isolation issues, internal room acoustic performance, and interfacing with teaching and industry commercial ergonomic needs (among others). This presentation will use the recently completed Berklee College of Music Studio Complex (Boston, MA) as its prime example and should be associated with a technical tour of the studios provided during the conference.
Acoustical design for a little big theater: Instituto Brincante
Authors: Nepomuceno José A.
Published: June 2017

The Brincante Institute located in São Paulo, Brazil, is a space devoted to the study and re-creation of the multitudinous Brazilian artistic manifestations and cultural heritage. The space Brincante occupied from 1990 to 2014 with a theater, shops, and classrooms was demolished to give place for a commercial building. A new building was designed and built for the “new” Brincante, thanks to the donation of different groups and crow funding campaign. The new house is a two stories construction that occupies a small land of 200 m2. The design challenges were great: tight budget, quality expectations, noisy environment, broad use program, and close neighbor constructions. The range of performances includes acoustic and amplified music, dance to choir. The challenges of acoustic design were the small theater for 100 seats and the rehearsal room, requiring excellent acoustical conditions and high sound isolation due to location specifics. The theater's reduced size helped to keep audience close to players and the sensation of envelopment and clarity. This paper describes the very simple and high performance solutions used for sound isolation and acoustical conditioning. Artists and public received the acoustics with great enthusiasm. The home gives Brincante the opportunity to keep alive.
Hospital noise mitigation
Authors: Doggett Felicia , San Souci Sooch
Published: June 2017

A review of the literature today concerning noise in hospitals, both public and peer review, points to a continual increase in noise complaints from medical staff and patients in hospitals. One would expect that things would be getting better by now, but this is not the case. Noise surveys that we have recently conducted suggest that though unsatisfactory conditions are widespread, a list of simple, cost effective solutions has proven to be effective. This paper presents an array of actual projects detailing the development of remedies for noise annoyance in hospitals in an effort to increase the comfort and performance of medical staff and patients.
Underwater ears and the physiology of impacts: Comparative liability for hearing loss in sea turtles, birds, and mammals
Authors: Ketten Darlene R.
Published: June 2017

From human and laboratory animal studies, we have extensive knowledge about mechanisms of hearing loss from noise as well as aging, trauma, genetic conditions, and disease. By contrast, little is known about causes of hearing loss in wild species. Although there is great concern for anthropogenic acoustic impacts in marine species, especially for marine mammals, we are far from a clear understanding of the potential scope of impacts on the thousands of marine species. We have acquired significant data on hearing in pinnipeds, cetaceans, and fish, but far less is known about hearing and possible impacts in turtles and seabirds and how or if they suffer irreparable hearing loss. This talk will review what is known about hearing loss mechanisms from human and animal studies and based on the comparisons for land and marine ears, how the combined data can aid us to understand how hearing may be impaired in marine animals. It will also examine the current evidence for natural loss processes (presbycusis, disease, and trauma) in marine animals and implications for our ability to estimate and mitigate hearing loss from underwater sound.
Sound sources in the marine environment
Authors: Lucke Klaus
Published: June 2017

Regulation of underwater sound requires a good understanding of the sound emitted from various sound sources into the marine environment. Underwater sound sources can be subdivided into three main categories: geological, biological, and anthropogenic sources. While regulation of underwater sound self-evidently applies solely to anthropogenic sound, contributions from the other categories need to be taken into account when assessing the potential influence of man-made sound on the marine fauna. In addition to focusing on single offshore operations, cumulative noise exposure and cumulative stressors are relevant aspects for the regulation of underwater sound and need to be considered too. In this presentation, the main underwater sound contributors from each category will be identified, and the related sounds characterized and compared in relation to the overall marine sound energy budget. Important implications with regard to physical parameters of sound will be briefly discussed. Current approaches to measuring, monitoring, and modeling underwater sound and how regulation can benefit from these different techniques will be reviewed.
Implementing NOAA Fisheries’ 2016 Marine Mammal Acoustic Guidance: Challenges and lessons learned
Authors: Scholik-Schlomer Amy R.
Published: June 2017

The National Oceanic and Atmospheric Administration’s (NOAA) first comprehensive Guidance addressing the effects of noise on marine mammal hearing is intended for use by NOAA managers and applicants to better predict acoustic exposures that have the potential to trigger certain requirements under various statutes (e.g., U.S. Marine Mammal Protection Act; Endangered Species Act). The Guidance was developed by compiling, interpreting, and synthesizing scientific information on the effects of anthropogenic sound on marine mammal hearing. The Guidance’s updated acoustic thresholds are more sophisticated than our previous thresholds. This added complexity is an important consideration for applicants who have formerly relied on more simple acoustic thresholds to evaluate potential impacts. Thus, the development of user-friendly tools is a fundamental issue for the regulatory community that is not often considered by most outside this group. As NOAA implements the Guidance, we have entered a new phase that consists of its own inherent issues and challenges associated with the practicality of employing more complex science to real-world applications. Throughout this process, NOAA has learned several valuable lessons, which will help improve the process of updating this document as well as drafting future guidance (e.g., marine mammal behavioral guidance; guidance for other protected species).
Assessing the effects of noise masking and transmission loss on dolphin occupancy rates reported by echolocation click loggers deployed on the eastern Scottish coast
Authors: Palmer Kaitln , Brookes Kate L. , Rendell Luke
Published: June 2017

C-PODs are commercially available echolocation click loggers used to monitor odontocete populations worldwide. Data from C-PODs have directly contributed to high-profile conservation efforts as well as provided major insights into cetacean behavior and habitat use. However, the “black-box” nature of the instruments poses a challenge to researchers seeking to validate data from these instruments. In this study, we simulate how changes in site-specific propagation conditions and ambient noise levels shift dolphin occupancy rates as reported by the C-POD. As part of the ECoMASS array, 10 calibrated continuous recorders (SM2Ms) were co-deployed with C-PODs in the North Sea. Transmission loss profiles, assumed dolphin source levels, and published C-POD performance metrics were combined to estimate the relationship between detection probability and ambient noise level at the 10 study sights. Bayesian models were then used to estimate dolphin occupancy rates with and without accounting for differences in detection probability. While absolute occupancy rates differed when detection probability was accounted for, relative trends in occupancy were generally consistent within the two models. These data suggest that, within the scope of the ECoMASS array, relative occupancy rates are somewhat robust to differences in transmission loss and ambient noise levels throughout the survey period and location.
Estimating geo-position and depth of echo-locating beaked whales using an array of drifting recorders
Authors: Barlow Jay , Griffiths Emily T. , Klinck Holger
Published: June 2017

An array of 8 drifting recorders were deployed in the Catalina Basin off Southern California to localize beaked whales. The drifting recorders with hydrophone pairs at 90-135 m were deployed along two parallel lines with ~1 km separation between recorders. The array was re-deployed daily at approximately the same location to maintain this array spacing. Cuvier’s beaked whales (Ziphius cavirostris) were detected on 26 occasions from their distinctive echo-location clicks. On 8 of these occasions, direct-path and surface-reflected signals were received on four or more drifting recorders, which allowed us to estimate location and depth of the whales. Average array tilt during these events was less than 0.2°, and always less than 0.6°. The same echolocation clicks were seldom received on more than two recorders, so we could not use methods that require TDOA measurements between recorders. We develop a novel method of 3-D localization using the vertical bearing angles estimated from the direct- and surface-reflected signals and use optimization methods to find the unique location and depth at which these angles converged. Detection ranges varied from 1.0 to 3.7 km (mean = 2.0, sd = 0.65), and depths of vocalizing animals varied from 696-1150 m (mean = 948, sd = 152).
A method of estimating the value of in situ surface tension on a bubble wall
Authors: Zhu Mengyang , Leighton Tim , Birkin Peter
Published: June 2017

The surface tension of a liquid is an important parameter for estimating and analyzing the processes that happen on the air/liquid interface, such as the air/sea gas exchange. Current methods of measuring surface tension concentrate on measuring its value at the top flat air/liquid interface. However, in cases where bubbles mediate oceanic processes (such as their contributions to air-to-sea transfers of mass, energy, and momentum), the value of surface tension that is needed (e.g., for placement in models of the evolution and persistence of sub-surface bubble clouds) is the instantaneous value on the bubble wall, as it moves through the ocean and potentially collects surface-active species onto the bubble wall. This paper outlines a method of estimating the value of this in situ surface tension, by insonifying a bubble and observing the onset of Faraday waves on a bubble wall. This new method was compared with a traditional ring method in various scenarios.
An acoustic study of sea ice behavior in a shallow, Arctic bay
Authors: Glowacki Oskar
Published: June 2017

Recent acceleration of sea ice decline observed in the Arctic Ocean draws attention to environmental factors driving this phenomenon. One of the main conclusions is a growing need for better understanding of sea ice drift, deformation, and fracturing. In response to that call, several ambient noise recordings were carried out in the coastal zone of Hornsund Fjord, Spitsbergen, in spring 2015 to study underwater acoustic signatures of sea ice behavior. The noise levels varied significantly with sea ice type and intensity of external forces. Low-frequency signatures were strongly related to tidal cycle, which manifested in much higher SPL values at low water. Compacted ice cover is periodically deformed and crushed, representing a significant contribution to the ambient noise field in the study site. Average noise levels at frequencies above 1 kHz are, in turn, considerably higher in front of marine-terminating glacier than in the neighboring, non-glacial bay. These differences, expanding with the rise of water temperature, are associated with melting of the ice cliff and generally unaffected by the presence of sea ice. [Work funded by the Polish National Science Centre, Grant No. 2013/11/N/ST10/01729.]
The masking of beluga whale (Delphinapterus leucas) sounds by icebreaker noise in the Arctic
Authors: Erbe Christine
Published: June 2017

Beluga whales are an Arctic and subarctic cetacean, with an overall “near threatened” conservation status, yet some populations are considered endangered. Apart from threats such as whaling, predation, contamination, and pathogens, underwater noise is of increasing concern. In the early 1990s, Fisheries & Oceans Canada started to fund research on underwater noise emitted by icebreakers and its bioacoustic impacts. In collaboration with the Vancouver Aquarium, beluga whales were trained for masked hearing experiments. Apart from measuring pure-tone audiograms in quiet conditions, animals were trained to listen for beluga vocalizations in different types of noise, including artificially created white noise, naturally occurring thermal ice-cracking noise, and an icebreaker’s propeller cavitation and bubbler system noise. Based on this data, software models for masking in beluga whales were developed. More than 20 years later, this dataset remains the only one on masking in cetaceans using both complex signals (actual vocalizations) and complex noise (actual recordings of Arctic ambient and anthropogenic noise)—highlighting both Dave Farmer’s foresight as well as perhaps his lesser-known escapades into marine mammal bioacoustics.
The upper ocean ambient sound field as a tool to address significant scientific and societal questions
Authors: Vagle Svein
Published: June 2017

David Farmer’s keen interest in understanding the dynamics of the upper-ocean and air-sea interaction convinced him that studying and using the naturally occurring high-frequency oceanic sound field would give additional insight into these processes. Breaking surface waves are important to ocean dynamics and were believed to be a significant source of the observed sound field. However, direct measurements were lacking. In the mid-1980s and onwards, David Farmer and his students developed a range of new observational techniques and instrumentation which would significantly improve our understanding of the sound field itself and how it relates to parameters such as wind speed and wave conditions, and as a tool to understanding the more fundamental physical processes of the upper ocean. All this research resulted in significant progress in our understanding of wave breaking, air-sea interaction, air-sea gas transfer, and indirectly to upper-ocean bubble distributions and dynamics, ice generated sound, and the role of anthropogenic noise on marine fauna. Here, we review key outcomes of this research and discuss how several components of Farmer et al.’s work now is being used to address significant societal issues with regard to the impacts of increasing levels of man-made underwater noise on marine life.
Eigenvalue analysis for acoustic multi-ports
Authors: Sack Stefan , Åbom Mats
Published: June 2017

Acoustic multi-ports are commonly used to describe the scattering (the transmission and reflection) and the source of aero-acoustic components in duct and pipe systems. The components are therefore modeled as “black-boxes,” assuming linear and time invariant systems. Using linear network theory, two components can be combined to a cascade for which the scattering and sources are predicted. This step, however, requires decoupled components; the flow disturbances downstream of an aero-acoustic source can be large and turbulences impinging on the downstream component may change its acoustic properties. In this presentation, we show how to use eigenvalue equations in order to investigate this so called “installation-effect” on both, the scattering and the source of induct components. The theoretical results are compared with measurements in order to conclude on the changing source and scattering mechanisms.
A numerical investigation of Helmholtz resonators in the presence of grazing flow by means of the lattice Boltzmann method
Authors: Spillere Andre M. , de Santana Neto José P. , da Silva Andrey R. , Cordioli Julio A.
Published: June 2017

Helmholtz resonators remain widely used in noise control. In applications such as aircraft engines and exhaust systems, the presence of a grazing flow significantly changes their behavior, and a correct prediction of their acoustic properties is essential to improve noise reduction. With the purpose of understanding the physical phenomena associated with the acoustic-flow interaction, the simulation of a single 2D Helmholtz resonator was considered by means of an in-house numerical code based on the lattice Boltzmann method (LBM). The results have been validated against published data based on both experimental results and direct numerical simulation (DNS) for normally incident acoustic waves in the absence of flow. The investigations will proceed by taking into account grazing acoustic waves in the presence of a grazing flow, similarly to the conditions found in a liner test rig. Efforts will be focused on typical aircraft engine inlet conditions, i.e., high Mach numbers and SPL. Both experimental and numerical results will be compared in terms of absorption coefficient and impedance.
Flow noise generation in a pipe bend
Authors: Knutsson Magnus , Vizzini Simone , Dybeck Maria , Åbom Mats
Published: June 2017

Noise generated by low Mach number flow in duct networks is important in many industrial applications. In the automotive industry, the two most important are the ventilation duct network and the engine exhaust system. Traditionally, design is made based on rule-of thumb or slightly better by simple semi-empirical scaling laws for flow noise. In many cases, strong curvatures and local deviations from circular cross-sections are created due to outer geometry restrictions. This can result in local relatively high flow velocities and complex flow separation patterns and as a result, rule-of thumb and scaling law methods can become highly inaccurate and uncertain. More advanced techniques based on time domain modelling of the fluid dynamics equations together with acoustic analogies can offer a better understanding of the local noise generation, the propagation and interaction with the rest of the system. This investigation contains a study on flow noise generation in a circular duct with a 90-degree bend carrying a low Mach number flow. Experimental results are presented and compared to numerical simulations, based on a combination of computational fluid dynamics and the acoustic analogies by Lighthill and Möhring, as well as semi-empirical models.
Attenuation measurements inside and at the output of a passive silencer equipped with parallel absorbing baffles
Authors: Kaiser Xavier , Brandt Sebastien , Meys Benoit , Plom Nicolas , Embrechts Jean-Jacques
Published: June 2017

The mock-up of a great passive silencer used for noise attenuation in industrial applications has been designed and tested in laboratory. This mock-up consists of three metal casing containing the noise source and several removable rails and supports, allowing the test of different configurations of parallel absorbing baffles. The output of the silencer radiates in an anechoic chamber in order to simulate free-field conditions. The acoustic attenuation has been measured not only at the output, but also inside the silencer, with a mobile microphone located at several positions along the axis. Also, the tested configurations include three types of absorbing “cushions” and several geometrical arrangements. The results show that the maximum insertion loss (dB) measured at the output of the silencer corresponds to frequencies between 800 Hz and 2.5 kHz and its value strongly depends on the air gaps between baffles. The measurements with the mobile microphone show a linear decrease of the sound pressure level with the distance along the axis (mainly between 100 Hz and 1 kHz), which corresponds to the depth of absorbing material involved in the attenuation. Finally, a comparison with a real-scale silencer is discussed.
Oscillatory brain activity in response to emotional sounds in musicians and non-musicians
Authors: Nolden Sophie , Rigoulot Simon , Jolicoeur Pierre , Armony Jorge L.
Published: June 2017

Emotions can be conveyed through a variety of channels in the auditory domain such as the human voice or music. Recent studies suggest that expertise in one sound category can impact the processing of emotional sounds in other sound categories. We focused here on how the neural processing of emotional information varies as a function of sound category and expertise of participants. Electroencephalogram (EEG) of 20 non-musicians and 17 musicians was recorded while they listened to speech prosody, vocalizations (such as screams and laughter), and musical sounds. The amplitude of EEG-oscillatory activity in the theta, alpha, beta, and gamma band was quantified and Independent Component Analysis (ICA) was used to identify underlying components of brain activity in each band. Sound category-dependent activations were found in frontal theta and alpha, as well as greater activation for musicians than for non-musicians. Differences in the beta band were mainly due to differential processing of speech. The results reflect musicians’ expertise in recognition of emotion-conveying music, which seems to also generalize to emotional expressions conveyed by the human voice, in line with previous accounts of effects of expertise on musical and vocal sounds processing.
Using functional magnetic resonance imaging to assess the emotional response to room acoustics
Authors: Lawless Martin S. , Vigeant Michelle C.
Published: June 2017

A previous pilot study by the authors demonstrated the potential of using neuroimaging techniques to investigate a listener’s emotional response to room acoustic conditions of varying preference. The hypothesis of the pilot study and the present work is that regions associated with reward and pleasure will activate when an individual listens to pleasing room acoustics contrasted with listening to unpleasant room acoustics. In this study, auralizations were generated in simulated room conditions ranging from anechoic to extremely reverberant with the expectation that the most-liked stimuli would have reverberation times between 1.0 and 2.8 s. Participants were screened based on their ability to discern differences in preference across the stimuli. Following the screening, eligible participants rated the stimuli according to overall preference in a mock MRI machine. The results from the mock MRI testing were used to identify each participant’s most-liked and most-disliked stimuli, and to familiarize the participants with the MRI environment. In a second session, this pair of stimuli, along with anechoic and scrambled-music stimuli were presented to the subjects in an MRI machine. Contrasts between these conditions were analyzed to investigate if activations were present in regions associated with reward processing, including the nucleus accumbens, caudate nucleus, and orbitofrontal cortex.
Trekking around ancestors of smart instruments
Authors: Besnainou Charles
Published: June 2017

In the present time, smart instruments are the ongoing revolution tying together acoustical instruments and computers. The concepts of electronic active control of structure are the heart of the process. The aim of this paper is to summarize more than one century of trials. Who remembers the “infinite sound” piano of Richard Eisenmann driven by electromagnetics and been touched, during the Industrial Art Exhibition in Munich in 1888, by Hermann von Helmholtz, and earlier the Pape’s enhanced piano with air blow? Some experiments revive the project as the E-bow dedicated for the steel-string guitar. Then, after a jump in the 1990’s as exercises for students on teaching feedback Proportional-Integral-Derivative analogical central heating regulator. On the cliff of the positive feedback applied for a xylophone bar, and so on just before numerical systems.
No latency feedback controller coupled to real-time physical models using programmable hardware
Authors: Pfeifle Florian
Published: June 2017

Over the last years, advances in technology and methodology made it possible to simulate and synthesize highly realistic finite difference (FD) models in real-time or close to real-time. Still, most conventional processing platforms introduce latency to the signal processing chain due to sequential processing and/or communication protocol timing and throughput restrictions. This can act as a severe penalty when developing expressive controller interfaces for large geometry physical models. Using field programmable gate array (FPGA) hardware enables highly customized interface and FD model designs that are able to meet hard real-time requirements even for large physical models. In this work, a modified five-string banjo coupled to a real-time physical modeling synthesis application running on an FPGA development board is presented. The proposed methodology is an extension of an existing PCIe enabled interface which was primarily developed for research applications. The new interface is aimed at facilitating expressive interaction for musical purposes. The bi-directional excitation and feedback is realized using standard electro-mechanical sensors and actuators, making it possible to connect the string vibration of the modified banjo to arbitrary geometries as well as capturing the response of the modeled structure and feeding it back to the acoustic instrument. FD-models of different shapes and materials are implemented resulting in physically impossible instrument configurations yielding unique tone production capabilities.
Audio-haptic interaction with modal synthesis models
Authors: Berdahl Edgar J.
Published: June 2017

Using a musical instrument that is augmented with haptic feedback, a performer can be enabled to haptically interact with a modal synthesis-based sound synthesizer. This subject is explored using the resonators object in Synth-A-Modeler. For synthesizing a single mode of vibration, the resonators object should be configured with a single frequency in Hertz, a single T60 exponential decay time in seconds, and a single equivalent mass in kg. Changing the mass not only changes the level of the output sound, it also changes how the mode feels when touched using haptic feedback. The resonators object can further be configured to represent a driving-point admittance corresponding to arbitrarily many modes of vibration. In this case, each mode of vibration is specified by its own frequency, decay time, and equivalent mass. Since the modal parameters can be determined using an automated procedure, it is possible to (within limits) approximately calibrate modal models using recordings of sounds that decay approximately exponentially. Various model structures incorporating the resonators object are presented in a variety of contexts. The musical application of these models is demonstrated alongside presentation of compositions that use them.
A trial investigation to understand the characteristics of soundscape in a busy town from the viewpoint of sound quality
Authors: Akita Takeshi
Published: June 2017

To reveal the characteristics of soundscape of a town that has an open and busy place like a shopping avenue, an investigation that requests subjects finding out attracted sounds and evaluating their sound quality when they walk around the town is tried. Eight subjects participated in the present investigation It was carried out at Kita-Senju town in Tokyo. Each subject was required to walk around assigned area that has busy shopping avenue and road, to write down the name of sound, to take the photograph of sound source, and to evaluate its sound quality when his attention was attracted by some sounds. Sound quality was evaluated by 5 step scales that inquired strength, fineness, and acuteness. Results show that there are many kinds of sound that has little strength impression except road traffic noise. On the other hand, the evaluated results for fineness and acuteness are different among sounds that are evaluated not so loud. They also show that there are many meaningless sounds and machine oriented noises. It is suggested that finding out and evaluation method for attracted sounds in busy areas make the characteristics of soundscape clear and it will contribute to create fine sonic environment.
Soundscape of Arctic settlements: Longyearbyen and Pyramiden
Authors: Czopek Dorota , Malecki Pawel , Piechowicz Janusz , Wiciak Jerzy
Published: June 2017

This paper presents the soundscape analysis of two settlements in Spitsbergen in Svalbard archipelago. The first one is the largest settlement in Spitsbergen, Longyearbyen, with population of about 2000 people. It is the administrative center of Svalbard with airport and the seat of Governor of Svalbard. The second one, Pyramiden, is Russian, coal-mining settlement closed in 1998. Since 2007 Pyramiden has become the tourist attraction with hotel and small museum. Only a few workers live there permanently. Two one-week research expeditions were organized to perform preliminary Arctic soundscape measurements. First, summer expedition during polar day and second winter-spring expedition during the transition period between the polar night and polar day. Long and short term sound pressure level measurements together with the ambisonic recordings of unique and typical sounds were made. Both qualitative assessment and quantitative analysis of the results were carried out. The identification and classification of the existing sound sources were conducted. Furthermore, noise maps of both places together with the comparative analysis were performed.
Assessment of the relation between psychoacoustic parameters and the subjective perception of urban soundscapes
Authors: de la Prida Daniel , Pedrero Antonio , Díaz César , Navacerrada María Ángeles
Published: June 2017

Since soundscapes are strongly related to the human perception, the sound pressure level does not seem to be a sufficient representative of a soundscape by itself. Therefore, the characterization of a soundscape might be improved by using psychoacoustic parameters. A study has been conducted and the relationship between psychoacoustic parameters and the subjective perception has been analyzed, for a collection of urban spaces. For that purpose, several locations at the city of Madrid have been selected, based on their main use and geometrical features. Then, binaural recordings have been made for several days and different seasons, which allow to observe the relevance of the behavioral differences for the same locations under different conditions. Psychoacoustic parameters, as well as sound pressure level, have been calculated for both the complete recordings and selected parts of them. A semantic differential listening test have been carried out to look for correlations between the calculated parameters and the subjective perception of a panel of participants. Finally, an automatic clustering is presented for the collection of locations. The adequacy of the proposed clustering method is evaluated by comparing the clusters to the psychoacoustic parameters and the subjective responses of the listening test.
Commercial space operations noise and sonic boom issues
Authors: Sizov Natalia
Published: June 2017

Commercial space transportation is a rapidly developing industry worldwide. The expansion of the space transportation infrastructure creates additional challenges to the National Airspace System. New launch facilities have and are being developed some of which co-locate with commercial airports. Rocket launch community noise impact requires adequate assessment and mitigation. New space vehicles encompass a wide range of design, aircraft geometry, and flight parameters. A database of operational launch profiles for rockets does not exist at this moment. The acoustical characteristic of these new vehicles may also differ from that of existing rockets or conventional aircraft. Spacecraft ascent sonic boom signatures have higher overpressure, longer duration and a bow shock. There are no standard methodologies for the environmental assessment of launch vehicles and sites. Developing and validating these models is an emerging field. In addition, the metrics used for community noise assessment for commercial aircraft are being used for commercial space operations and may not be appropriate for such use. The existing gaps in rocket launch community noise assessment, technical and regulatory requirements, and current steps the FAA is undertaking to establish an environmental regulatory framework for the commercial space operations will be discussed.
Mapping nonlinear infrasound penetration into a shadow zone: Results from rocket motor blasts at the Utah Test and Training Range
Authors: de Groot-Hedlin Catherine
Published: June 2017

Each summer, large-scale detonations are carried out at the Utah Test and Training Range (UTTR) west of Salt Lake City. In 2016, acoustic sensors were placed at ranges up to 90 km east of the UTTR test site. The frequencies of the recorded signals indicate that they are infrasonic waves. The travel times imply that they are direct arrivals although the sensors lie within a shadow zone. Finally, the signal amplitudes indicate that acoustic propagation is nonlinear near the source. Consequently, numerical simulations that account for diffraction, and the effects of strong shocks are required to accurately map infrasound propagation into this region. A finite difference time-domain infrasound propagation method is applied to these signals. The algorithm relies on the assumption that the environmental model is azimuthally symmetric about the source location, allowing for efficient numerical computation of acoustic propagation from a spherical source. For each detonation, numerical computations are performed along a series of azimuths from the shot position, using accurate weather and topography along each path. The results show that infrasound penetration into the shadow zone is accurately predicted. The synthesized over-pressures are positive correlated with observed pressure amplitudes, to an accuracy of 8 dB.
Acoustic/Infrasonic analysis and modeling of thunder from a long-term recording in Southern France
Authors: Lacroix Arthur , Farges Thomas , Marchiano Régis , Coulouvrat François
Published: June 2017

Thunder produces complex signals with a rich infrasonic and audible frequency spectrum. These signals depend both on the source and the propagation to the observer. However, there is no mutual agreement on the link between the observed spectral content and the generation mechanisms. The objectives of this study is to provide additional experimental and theoretical investigations, especially on the return stroke, based on a database of several thousands of acoustic and electromagnetic signals recorded in Southern France during autumn 2012 (HyMeX campaign). It contains a sufficient number of events close to the source (<1 km) to minimize propagation effects and to focus on the source effects. Source localization and lightning acoustical reconstruction indicate that infrasonic and low frequency audible part (1-40 Hz) of the spectrum show no clear differences between the return stroke and the intracloud discharges. These observations are compatible with a source mechanism due to the thermal expansion associated to the sudden heating of the air in the lightning channel. An original model inspired by Few's string pearl theory has been developed. It shows that the tortuous channel geometry explains at least partly the low frequency content of observed thunder spectrum.
Modeling sound externalization based on listener-specific spectral cues
Authors: Baumgartner Robert , Majdak Piotr , Colburn H. Steven , Shinn-Cunningham Barbara
Published: June 2017

Sound sources in natural environments are usually perceived as externalized auditory objects located outside the head. In contrast, when listening via headphones or hearing-assistive devices, sounds are often heard inside the head, presumably because they are filtered in a way inconsistent with normal experience. Previous results suggest that high-frequency spectral cues arising from the listener-specific filtering by the pinnae are particularly important for sound externalization, but this has not been confirmed in a quantitative perceptual model yet. Here, we present a model designed to predict sound externalization related to the spectral-cue salience in free field. The modeling results are compared to results from various behavioral studies testing the effect of low-pass filtering, non-individualized head-related transfer functions, and behind-the-ear microphone casing in hearing-assistive devices. We will discuss the limitations of previous experimental designs and existing modeling approaches, including fundamental issues of model fitting.