W.M. To – wmto@ipm.edu.mo Macao Polytechnic Institute, Macao SAR, China. A. Chung – ac@smartcitymakter.com Smart City Maker, Denmark. B. Schulte-Fortkamp – b.schulte-fortkamp@tu-berlin.de Technische Universität Berlin, Berlin, Germany.
Popular version of paper 2aNS, “How virtual reality technologies can enable better soundscape design” Presented Tuesday morning, November 29, 2016 172nd ASA Meeting, Honolulu
The quality of life including good sound quality has been sought by community members as part of the smart city initiative. While many governments have placed special attention to waste management, air and water pollution, acoustic environment in cities has been directed toward the control of noise, in particular, transportation noise. Governments that care about the tranquility in cities rely primarily on setting the so-called acceptable noise levels i.e. just quantities for compliance and improvement [1]. Sound quality is most often ignored. Recently, the International Organization for Standardization (ISO) released the standard on soundscape [2]. However, sound quality is a subjective matter and depends heavily on the perception of humans in different contexts [3]. For example, China’s public parks are well known to be rather noisy in the morning due to the activities of boisterous amateur musicians and dancers – many of them are retirees and housewives – or “Da Ma” [4]. These activities would cause numerous complaints if they would happen in other parts of the world, but in China it is part of everyday life.
According to the ISO soundscape guideline, people can use sound walks, questionnaire surveys, and even lab tests to determine sound quality during a soundscape design process [3]. With the advance of virtual reality technologies, we believe that the current technology enables us to create an application that immerses designers and stakeholders in the community to perceive and compare changes in sound quality and to provide feedback on different soundscape designs. An app has been developed specifically for this purpose. Figure 1 shows a simulated environment in which a student or visitor arrives the school’s campus, walks through the lawn, passes a multifunctional court, and get into an open area with table tennis tables. She or he can experience different ambient sounds and can click an object to increase or decrease the volume of sound from that object. After hearing sounds at different locations from different sources, the person can evaluate the level of acoustic comfort at each location and express their feelings toward overall soundscape. She or he can rate the sonic environment based on its degree of perceived loudness and its level of pleasantness using a 5-point scale from 1 = ‘heard nothing/not at all pleasant’ to 5 = ‘very loud/pleasant’. Besides, she or he shall describe the acoustic environment and soundscape using free words because of the multi-dimensional nature of sonic environment.
Figure 1. A simulated soundwalk in a school campus.
To, W. M., Mak, C. M., and Chung, W. L.. Are the noise levels acceptable in a built environment like Hong Kong? Noise and Health, 2015. 17(79): 429-439.
ISO. ISO 12913-1:2014 Acoustics – Soundscape – Part 1: Definition and Conceptual Framework, Geneva: International Organization for Standardization, 2014.
Kang, J. and Schulte-Fortkamp, B. (Eds.). Soundscape and the Built Environment, CRC Press, 2016.
Suzi Wiseman – sw1210txstate@gmail.com Texas State University-San Marcos Environmental Geography 601 University Drive, San Marcos, Texas 78666 Preston S. Wilson – wilsonps@austin.utexas.edu University of Texas at Austin Mechanical Engineering Department 1 University Station C2200 Austin, TX 78712
Popular version of paper 2aAB7, “Nocturnal peace at a Conservation Center for Species Survival?” Presented Tuesday morning, May 19, 2015 at 10.15am 169th ASA Meeting, Pittsburgh
The acoustic environment is essential to wildlife, providing vital information about prey and predators and the activities of other living creatures (biophonic information) (Wilson, 1984), about changing weather conditions and occasionally geophysical movement (geophonic), and about human activities (anthrophonic) (Krause 1987). Small sounds can be as critical as loud, depending on the species trying to listen. Some hear infrasonically (too low for humans, generally considered below 20 Hz), others ultrasonically (too high, above 20 kHz). Biophonic soundscapes frequently exhibit temporal and seasonal patterns, for example a dawn “chorus”, mating and nurturing calls, diurnal and crepuscular events.
Some people are attracted to large parks due in part to their “peace and quiet” (McKenna 2013). But even in a desert, a snake may be heard to slither or wind may sigh between rocks. Does silence in fact exist? Finding truly quiet places, in nature or the built environment is increasingly difficult. Even in our anechoic chamber, which was purpose built to be extremely quiet, located in the heart of our now very crowded and busy urban campus, we became aware of infrasound that penetrated, possibly from nearby construction equipment or from heavy traffic that was not nearly as common when the chamber was first built more than 30 years ago. Is anywhere that contains life actually silent?
Figure 1: In the top window, the waveform in blue indicates the amplitude over time each occasion that a pulse of sound was broadcast in the anechoic chamber, as shown in the spectrogram in the lower window, where the frequency is shown over the same time, and the color indicates the intensity of the sound (red being more intense than blue). Considerable very low frequency sound was evident and can be seen between the pulses in the waveform (which should be silent), and throughout at the bottom of the spectrogram. The blue dotted vertical lines show harmonics that were generated within the loudspeaker system. (Measurements shown in this study were by a Roland R26 recorder with Earthworks M23 measurement microphones with frequency response 9Hz to 23kHz ±1/-3dB)
As human populations increase, so do all forms of anthrophonic noise, often masking the sounds of nature. Does this noise cease at night, especially if well away from major cities and when humans are not close-by? This study analyzed the soundscape continuously recorded beside the southern white rhinoceros (Ceratotherium simum simum) enclosure at Fossil Rim Wildlife Center, about 75 miles southwest of Dallas Texas for a week during Fall 2013, to determine the quietest period each night and the acoustic environment in which these periods tended to occur. Rhinos hear infrasound, so the soundscape was measured from 0.1 Hz to 22,050 kHz. Since frequencies below 9 Hz still need to be confirmed however, these lowest frequencies were removed from this portion of the study.
Figure 2: Part of the white rhinoceros enclosure of Fossil Rim Wildlife Center, looking towards the tree line where the central recorder was placed
Figure 3: The sound pressure level throughout a relatively quiet day at the rhino enclosure. The loudest sounds were normally vehicles, machinery, equipment, aircraft, and crows. The 9pm weather front was a major contrast.
Figure 3 illustrates the rhythm of a day at Fossil Rim as shown by the sound level of a fairly typical 24 hours starting from midnight, apart from the evening storm. As often occurred, the quietest period was between midnight and the dawn chorus.
While there were times during the day when birds and insects were their most active and anthrophonic noise was not heard above them, it was discovered that all quiet periods contained anthrophonic noise, even at night. There was generally a low frequency, low amplitude hum – at times just steady and machine-like and not yet identified – and depending on wind direction, often short hums from traffic on a state highway over a mile away. Quiet periods ranged from a few minutes to almost an hour, usually eventually broken by anthrophonic sounds such as vehicles on a nearby county road, high aircraft, or dogs barking on neighboring ranches. However there was also a strong and informative biophonic presence – from insects to nocturnal birds and wildlife such as coyotes, to sounds made by the rhinos themselves and by other species at Fossil Rim. Geophonic intrusions were generally wind, thunder or rain, possibly hail.
The quietest quarter hour was about 4am on the Friday depicted in figure 3, but even then the absolute sound pressure level averaged 44.7 decibels, about the level of a quiet home or library. The wind was from the south southeast around 10 to 14 mph during this time. Audio clip 1 is the sound of this quiet period.
Figure 4: The quietest quarter hour recorded at Fossil Rim appears between the vertical red selection lines, with an average absolute sound pressure level of 44.5 decibels. The fairly constant waveform shown in blue in the top graph and the low frequency noise at the bottom of the spectrogram seemed to comprise the machine-like hum, the distant traffic hum which varies over time, and insects. The blue flashes between 3 and 5 Hz were mainly bird calls.
By contrast, the loudest of the “quietest nightly periods” was less than six minutes long, around 5am on Wednesday 23rd October, as shown between the vertical red lines in figure 5. Despite being the quietest period that night, it averaged a sound pressure level of 55.5 decibels, which is roughly the equivalent of a spoken conversation.
Figure 5: The loudest “quietest period each night” reveals broadband machine noise (possibly road work equipment somewhere in the district?) which continued for some hours and appears as the blue flecks across all frequencies. The horizontal blue line at 16.5 kHz is characteristic of bats. All species identification is being left to biologists for confirmation. Audio clip 2 is this selection.
Either side of the “quiet” minutes were short bursts of low frequency but intense truck and/or other machine noise indicated in red, some of which partially covered a clang when a rhino hit its fence with its horn, and distant barks, howls, moos and other vocalizations. The noise may have masked the extremely low frequency hums and insects that had been apparent on other nights or to have caused the insects to cease their activity. The strata below 2.5 kHz appear more ragged, indicating they are not being produced in such a uniform way as on quieter nights, and they are partially covered by the blue flecks of machine noise. However the strata at 5.5, 8.5, 11 and especially at 16.5 kHz that appeared on other nights are still evident. They appear to be birds, insects and bats. Audio clip 3 contains the sounds that broke this quiet period.
At no point during the entire week was anything closely approaching “silence” apparent. Krause reports that healthy natural soundscapes comprise a myriad of biophony, and indeed the ecological health of a region can be measured by its diverse voices (Krause 1987). However if these voices are too frequently masked or deterred by anthrophonic noise, animals may be altered behaviorally and physiologically (Pater et al, 2009), as the World Health Organization reports to be the case with humans who are exposed to chronic noise (WHO 1999). Despite some level of anthrophonic noise at most times, Fossil Rim seems to provide a healthy acoustic baseline since so many endangered species proliferate there.
Understanding soundscapes and later investigating any acoustic parameters that may correlate with animals’ behavior and/or physiological responses may lead us to think anew about the environments in which we hold animals captive in conservation, agricultural and even domestic environments, and about wildlife in parts of the world that are being increasingly encroached upon by man.
References: Krause, B. 1987. The niche hypothesis. Whole Earth Review . Wild Sanctuary. ———. 1987. Bio-acoustics: Habitat ambience & ecological balance. Whole Earth Review. Wild Sanctuary. McKenna, Megan F., et al. “Patterns in bioacoustic activity observed in US National Parks.” The Journal of the Acoustical Society of America 134.5 (2013): 4175-4175. Pater, L. L., T. G. Grubb, and D. K. Delaney. 2009. Recommendations for improved assessment of noise impacts on wildlife. The Journal of Wildlife Management 73:788-795. Wilson, E. O. 1984. Biophilia. Harvard University Press. World Health Organization. “Guidelines for community noise”. WHO Expert Taskforce Meeting. London. 1999.
Irene van Kamp, (irene.van.kamp@rivm.nl) Elise van Kempen, Hanneke Kruize, Wim Swart National Institute for Public Health and the Environment Netherlands Pobox 1 Postvak 10 3720 BA BILTHOVEN Netherlands Phone +31629555704
Popular version of paper in session 2aNSa, “Soundscapes and human restoration in green urban areas” Presented Tuesday morning, May 19, 2015, 9:35 AM, Commonwealth 1 169th ASA Meeting, Pittsburgh
Worldwide there is a revival of interest in the positive effect of landscapes, green and blue space, open countryside on human well-being, quality of life, and health especially for urban dwellers. However, most studies do not account for the influence of the acoustic environment in these spaces both in a negative and positive way. One of the few studies in the field, which was done by Kang and Zhang (2010) identified relaxation, communication, dynamics and spatiality as the key factors in the evaluation of urban soundscapes. Remarkable is their finding that the general public and urban designers clearly value public space very different. The latter had a much stronger preference for natural sounds and green spaces than the lay-observers. Do we as professionals tend to exaggerate the value of green and what characteristics of urban green space are key to health, wellbeing and restoration? And what role does the acoustic quality and accompanying social quality play in this? In his famous studies on livable streets Donald Appleyard concluded that in heavy traffic streets the number of contacts with friends, acquaintances and the amount of social interaction in general was much lower. Also people in busy streets had a tendency to describe their environment as being much smaller than their counterparts in quiet streets did. In other words, the acoustic quality affects not only our wellbeing and behavior but also our sense of territory, social cohesion and social interactions. And this concerns all of us: citing Appleyard “nearly everyone in the world lives in a street”.
There is evidence that green or natural areas/wilderness/ or urban environments with natural elements as well as areas with a high sound quality can intrinsically provide restoration through spending time there. Also merely the knowledge that such quiet and green places are available seems to work as a buffer effect between stress and health (Van Kamp, Klaeboe, Brown, and Lercher, 2015 : in Jian Kang and Brigitte Schulte-Fortkamp (Eds) in press).
Recently a European study was performed into the health effect of access and use of green area in four European cities of varying size in Spain, the UK, Netherlands and Lithuania)
At the four study centers people were selected from neighborhoods with varying levels of socioeconomic status and green and blue space. By means of a structured interview information was gathered about availability, use and importance of green space in the immediate environment as well as the sound quality of favorite green areas used for physical activity, social encounters and relaxation. Data are also available about perceived mental/physical health and medication use. This allowed for analyzing the association between indicators of green, restoration and health, while accounting for perceived soundscapes in more detail. In general there are four mechanisms assumed that lead from green and tranquil space to health: via physical activity, via social interactions and relaxation and finally via reduced levels of traffic related air and noise pollution. This paper will explore the role of sound in the process which leads from access and use of green space to restoration and health. So far this aspect has been understudied. There is some indication that certain areas contribute to restoration more than others. Most studies address the restorative effects of natural recreational areas outside the urban environment. The question is whether natural areas within, and in the vicinity of, urban areas contribute to psycho-physiological and mental restoration after stress as well. Does restoration require the absence of urban noise?
Example of an acoustic environment – a New York City Park – with potential restorative outcomes (Photo: A.L. Brown)
Brigitte Schulte-Fortkamp – b.schulte-fortkamp@tu-berlin.de Technical University Berlin Institute of Fluid Mechanics and Engineering Acoustics -Psychoacoustics and Noise effects – Einsteinufer 25 10587 Berlin -Germany
Popular version of paper 2aNSa1, “Soundscape as a resource to balance the quality of an acoustic environment” Tuesday morning, May 19, 2015, 8:35 AM, Commonwealth 1 169th ASA Meeting, Pittsburgh Pennsylvania
Preface Soundscape studies investigate and find increasingly better ways to measure and hone the acoustic environment. Soundscape offers the opportunity for multidisciplinary working, bringing together science, medicine, social studies and the arts – combined, crucially, with analysis, advice and feedback from the ‘users of the space’ as the primary ‘experts’ of any environment – to find creative and responsive solutions for protection of living places and to enhance the quality of life.
The Soundscape concept was introduced as a scope to rethink the evaluation of “noise” and its effects. The challenge was to consider the limits of acoustic measurements and to account for its cultural dimension.
The recent international standard ISO 12913-1 Acoustics — Soundscape —Part 1: Definition and conceptual framework Acoustique – Paysage sonore -Partie 1: Définition et cadre conceptual clarifies soundscape as an “acoustic environment as perceived or experienced and/or understood by a person or people, in context”
Figure 1 — Elements in the perceptual construct of soundscape
Soundscape suggests exploring noise in its complexity and its ambivalence and its approach towards sound to consider the conditions and purposes of its production, perception, and evaluation, to understand evaluation of noise/ sound as a holistic approach.
To discuss the contribution of Soundscape research into the area of Community noise research means to focus on the meaning of sounds and its implicit assessments to contribute to the understanding that the evaluation through perceptual effects is a key issue.
Using the resources – an example- Soundscape Approach Public Space Perception and Enhancement Drawing on Experience in Berlin Figure 2 – Soundscape Nauener Platz
The concept of development of the open pace relies on the understanding that people living in the chosen are the “real” experts concerning the evaluation of this place according to their expectations and experiences in the respective area. The intention of scientific research here is to learn about the meaning of the noise with respect to people’s living situation and to implement the adequate procedure to open the “black box” of people’s mind.
Therefore, the aim was to get residents involved through workshops to get access to the different social groups. Figure 3 – Participation and Collaboration Figure 4 – The concept of evaluation
Interdisciplinarity is considered as a must in the soundscape approach. In this case it was concerned with the collaboration of architects, acoustics engineers, environmental health specialists, psychologists, social scientists, and urban developers. The tasks are related to the local individual needs and are open to noise sensitive and other vulnerable groups. It is also concerned with cultural aspects and the relevance of natural soundscapes – sometimes referred to as quiet areas – which is obviously related to the highest level of needs. Figure 5 – Soundscape – an interactive approach using the resources
Improving local soundscape quality? Obviously, these new approaches and methods make it possible to learn about the process of perception and evaluation sufficiently as they take into account the context, ambiance, the usual interaction between noise and listener and the multidimensionality of noise perception.
By contrast, conventional methods often reduce the complexity of reality on controllable variables, which supposedly represent the scrutinized object. Furthermore, traditional tests neglect frequently the context-dependency of human perception; they only provide artificial realities and diminish the complexity of perception on merely predetermined values, which do not completely correspond with perceptual authenticity. However, perception and evaluations entirely depend on the respective influences of the acoustic and non-acoustic modifiers.
Following the comments and group discussion and also the results from the narrative interviews it could be defined why people prefer some places over the public place and why not. It also became clear how people experience the noise in the distance from the road and also with respect to social life and social control. One of the most important findings here is how people react to low frequency noise at the public place and how experiences and expectations work together. It becomes obvious that the most wanted sound in this area is based on wishes to escape the road traffic noise through natural sounds. Figure 6 – Selected sounds for audio islands
Reshaping the place based on people’s expertise Relying on the combined evaluation procedures the place was reshaped installing a gabion wall along one of the main roads and further more audio islands like have been built that integrated the sounds people would like to enjoy when using the place. While the gabion wall protects against noise around the playground, the new installed audio islands provide nature sounds as selected by the people involved in the Soundscape approach. Figure 7 – Installation of the sounds
Conclusions Figure 8 – The new place
The process of tuning of urban areas with respect to the expertise of people’s mind and quality of life is related to the strategy of triangulation and provides the theoretical frame with regard to the solution of e.g. the change in an area. In other words: Approaching the field in this holistic manner is generally needed.
An effective and sustainable reduction of the number of highly annoyed people caused by noise is only possible with further scientific endeavors in the area of methods development and research of noise effects. Noise maps providing further information can help to obtain a deeper understanding of noise reactions and can help to reliably identify perception-related hot spots. Psychoacoustic maps are particularly interesting in areas where the noise levels are marginal below the noise level limits and offer an additional interpretation help with respect to the identification of required noise abatement measures.
But, the expertise of people involved will provide meaningful information. Soundwalks as an eligibly instrument for exploring urban areas by minds of the “local experts” as measuring device open a field of data for triangulation. These techniques in combination allow giving meaning to the numbers and values of recordings and their analysis to understand the significance of sound and noise as well as the perception of Soundscapes by its resources. tags: soundscape, acoustics, people, health
REFERENCES J. Kang, B. Schulte-Fortkamp (editors) Soundscape and the Built Environment CRC Press | Taylor & Francis Group, in print B. Schulte-Fortkamp, J. Kang (editors) Special Issue on Soundscape, JASA 2012 R. M. Schafer, “The Soundscape. Our sonic environment and the tuning of the world.” Rochester, Vermont: Destiny Books, (1977). B. Hollstein, “Qualitative approaches to social reality: the search for meaning” in: John Scott & Peter J. Carrington (Eds.): Sage handbook of social network analysis. London/Newe Dehli: Sage. (2012) R. M. Schafer, “The Book of Noise” (Price Milburn Co., Lee, Wellington, NZ, (1973). B. Truax, (ed.) „Handbook for Acoustic Ecology” (A.R.C. Publication, Vancouver, (1978). K. Hiramatsu, “Soundscape: The Concept and Its Significance in Acoustics,” Proc. ICA, Kyoto, 2004. A. Fiebig, B. Schulte-Fortkamp, K. Genuit, „New options for the determination of environmental noise quality”, 35th International Congress and Exposition on Noise Control Engineering INTER-NOISE 2006, 04.-06.December 2006, Honolulu, HI. P. Lercher, B. Schulte-Fortkamp, “Soundscape and community noise annoyance in the context of environmental impact assessments,” Proc. INTER-NOISE 2003, 2815-2824, (2003). B. Schulte-Fortkamp, D. Dubois: (editors) Acta Acustica united with Acustica, Special Issue, Recent advances in Soundscape research, Vol 92 (6), (2006). R. Klaboe, et. al. „Änderungen in der Klang- und Stadtlandschaft nach Änderung von Straßenverkehrsstraßen im Stadtteil Oslo-Ost“, Fortschritte der Akustik, Oldenburg, (2000).
Glasgow Caledonian University School of Engineering and Built Environment 70 Cowcaddens Road Glasgow United Kingdom G4 0BA
Popular version of paper 5aNS6 Presented Friday morning, October 31st 2014 168th ASA Meeting, Indianapolis
The term ‘soundscape’ is widely used to describe the sonic landscape and can be considered the auditory equivalent of a visual landscape. Current soundscape research looks into the view of sound assessment in terms of perception and has been the subject of large scale projects such as the Positive Soundscapes Project (Davies et al. 2009) i.e. the emotional attributes associated with particular sounds. This research addresses the limitations of current noise assessment methods by taking into account the relationship between the acoustic environment and the emotional responses and behavioural characteristics of people living within it. Related research suggests that a variety of objective and subjective factors influence the effects of exposure to noise, including age, locale, cross-cultural differences (Guyot at el. 2005) and the time of year (Yang and Kang, 2005). A key aspect of this research area is the subjective effect of the soundscape on the listener. This paradigm emphasises the subjective perception of sound in an environment – and whether it is perceived as being positive or negative. This approach dovetails with advancing sound and music classification research which aims to categorise sounds in terms of their emotional impact on the listener.
Annoyance is one of the main factors which contribute to a negative view of environmental noise, and can lead to stress-related health conditions. Subjective perception of environmental sounds is dependent upon a variety of factors related to the sound, the geographical location and the listener. Noise maps used to communicate information to the public about environmental noise in a given geographic location are based on simple noise level measurements, and do not include any information regarding how perceptually annoying or otherwise the noise might be.
Figure 1 Selected locations for recording – image courtesy of Scottish Noise Mapping
This study involved subjective assessment by a large panel of listeners (N=167) of a corpus of sixty pre-recorded urban soundscapes collected from a variety of locations around Glasgow City Centre (see figure 1). Binaural recordings were taken at three points during each 24 hour period in order to capture urban noise during day, evening and night. Perceived annoyance was measured using Likert and numerical scales and each soundscape measured in terms of arousal and positive/negative valence (see figure 2).
Figure 2 Arousal/Valance Circumplex Model Presented in Listening Tests
Coding of each of the soundscapes would be essential process in order to test the effects of the location on the variables provided by the online survey namely annoyance score (verbal), annoyance score (numeric), quadrant score, arousal score, and valence score. The coding was based on the environment i.e. urban (U), semi-open (S), or open (O); the density of traffic i.e. high (H), mid (M), low (L); and the distance form the main noise source (road traffic) using two criteria >10m (10+) and <10m (10-). The coding resulted in eight different location types; UH10-, UH10+, UM10+, UL10-, SM10+, SL10-, SL10+, and OL10+.
To capture quantitative information about the actual audio recordings themselves, the MIRToolkit for MATLAB was used to extract acoustical features from the dataset. Several functions were identified that could be meaningful for measuring the soundscapes in terms of loudness, spectral shape, but also rhythm, which could be thought of in not so musical terms but as the rate and distribution of events within a soundscape.
As expected, correlations between extracted features and locations suggest where there are many transient events, higher energy levels, and where the type of events include harsh and dissonant sounds i.e. heavy traffic, resulted in higher annoyance scores and higher arousal scores but perceived more negatively than quiet areas. In those locations where there are fewer transient events, lower energy levels, and there are less harsh and possibly more positive sounds i.e. birdsong, resulted in lower annoyance scores and lower arousal scores as well as being perceived more positively than busy urban areas. The results shed light on the subjective annoyance of environmental sound in a range of locations and provide the reader with an insight as to what psychoacoustic features may contribute to these views of urban soundscapes.
References
Davies, W., Adams, M., Bruce, N., Cain, R., Jennings, P., Carlyle, A., … Plack, C. (2009, October 26). A positive soundscape evaluation system. Retrieved from http://usir.salford.ac.uk/2468/1/Davies_et_al_soundscape_evaluation_euronoise_2009.pdf
Guyot, F., Nathanail, C., Montignies, F., & Masson, B. (2005). Urban sound environment quality through a physical and perceptive classification of sound sources : a cross-cultural study Methodology.
Yang, W., & Kang, J. (2005). Soundscape and Sound Preferences in Urban Squares: A Case Study in Sheffield. Journal of Urban Design, 10(1), 61–80. doi:10.1080/13574800500062395
