Department of Music Acoustics, University of Music and Performing Arts Vienna, Vienna, Vienna, 1030, Austria
Alex Hofmann
Department of Music Acoustics
University of Music and Performing Arts Vienna
Vienna, Vienna, 1030
Austria
Popular version of 5aMU6 – Two-dimensional playability maps for single-reed woodwind instruments
Presented at the 185 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0023675
Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.
Musicians show incredible flexibility when generating sounds with their instruments. Nevertheless, some control parameters need to stay within certain limits for this to occur. Take for example a clarinet player. Using too much or too little blowing pressure would result in no sound being produced by the instrument. The required pressure value (depending on the note being played and other instrument properties) has to stay within certain limits. A way to study these limits is to generate ‘playability diagrams’. Such diagrams have been commonly used to analyze bowed-string instruments, but may be also informative for wind instruments, as suggested by Woodhouse at the 2023 Stockholm Music Acoustics Conference. Following this direction, such diagrams in the form of playability maps can highlight the playable regions of a musical instrument, subject to variation of certain control parameters, and eventually support performers in choosing their equipment.
One way to fill in these diagrams is via physical modeling simulations. Such simulations allow predicting the generated sound while slowly varying some of the control parameters. Figure 1 shows such an example, where a playability region is obtained while varying the blowing pressure and the stiffness of the clarinet reed. (In fact, the parameter varied on the y-axis is the effective stiffness per unit area of the reed, corresponding to the reed stiffness after it has been mounted on the mouthpiece and the musician’s lip is in contact with it). Black regions indicate ‘playable’ parameter combinations, whereas white regions indicate parameter combinations, where no sound is produced.
Figure 1: Pressure-stiffness playability map. The black regions correspond to parameter combinations that generate sound.
One possible observation is that, when players wish to play with a larger blowing pressure (resulting in louder sounds) they should use stiffer reeds. As indicated by the plot, for a reed of stiffness per area equal to 0.6 Pa/m (soft reed) it is not possible to generate a note with a blowing pressure above 2750 Pa. However, when using a harder reed (say with a stiffness of 1 Pa/m) one can play with larger blowing pressures, but it is impossible to play with a pressure lower than 3200 Pa in this case. Varying other types of control parameters could highlight similar effects regarding various instrument properties. For instance, playability maps subject to different mouthpiece geometries could be obtained, which would be valuable information for musicians and instrument makers alike.
Popular version of 1aSC2 – Retroflex nasals in the Mai-Ndombe (DRC): the case of nasals in North Boma B82
Presented at the 185th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0022724
Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.
“All language sounds are equal but some language sounds are more equal than others” – or, at least, that is the case in academia. While French i’s and English t’s are constantly re-dotted and re-crossed, the vast majority of the world’s linguistic communities remain undocumented, with their unique sound heritage gradually fading into silence. The preservation of humankind’s linguistic diversity relies solely on detailed documentation and description.
Over the past few years, a team of linguists from Ghent, Mons, and Kinshasa have dedicated their efforts to recording the phonetic and phonological oddities of southwest Congo’s Bantu varieties. Among these, North Boma (Figure 1) stands out for its display of rare sounds known as “retroflexes”. These sounds are particularly rare in central Africa, which mirrors a more general state of under-documentation of the area’s sound inventories. Through extensive fieldwork in the North Boma area, meticulous data analysis, and advanced statistical processing, these researchers have unveiled the first comprehensive account of North Boma’s retroflexes. As it turns out, North Boma retroflexes are exclusively nasal, a striking typological circumstance. Their work, presented in Sydney this year, not only enriches our understanding of these unique consonants but also unveils potential historical implications behind their prevalence in the region.
Figure 1 – the North Boma area
The study highlights the remarkable salience of North Boma’s retroflexes, characterised by distinct acoustic features that sometimes align and sometimes deviate from those reported in the existing literature. This is clearly shown in Figure 2, where the North Boma nasal space is plotted using a technique known as “Multiple Factor Analysis” allowing for the study of small corpora organised into clear variable groups. As can be seen, their behaviour differs greatly from that of the other nasals of North Boma. This uniqueness also suggests that their presence in the area may stem from interactions with long-lost hunter-gatherer forest languages, providing invaluable insights into the region’s history.
Figure 2 – MFA results show that retroflex and non-retroflex nasals behave very differently in North Boma
Extraordinary sound patterns are waiting to be discovered in the least documented language communities of the world. North Boma serves as just one compelling example among many. As we navigate towards an unprecedented language loss crisis, the imperative for detailed phonetic documentation becomes increasingly evident.
Macao Polytechnic University, R. de Luís Gonzaga Gomes, Macao, Macao, 00000, Macao
Andy Chung
Popular version of 3aNSb – Noise Dynamics in City Nightlife: Assessing Impact and Potential Solutions for Residential Proximity to Pubs and Bars
Presented at the 185 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0023229
Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.
Picture a typical evening in the heart of a bustling city: pubs and bars come alive, echoing with laughter, music, and the clink of glasses. These hubs of social life create a vibrant tapestry of sounds. But what happens when this symphony overshadows the tranquility of those living just around the corner?
Image courtesy of Kvikoo, Singapore
Our journey begins in the lively interiors of these establishments. In countries rich in nightlife, you’ll find a high concentration of pubs and bars – sometimes up to 150 per 100,000 people. Inside a pub in Hong Kong, for instance, noise levels can soar to 80 decibels during peak hours, akin to the din of city traffic. Even during ‘happy hours,’ the decibel count hovers around 75, still significant.
But let’s step outside these walls. Here, the story takes a different turn. In residential areas adjacent to these nightspots, the evening air is often filled with an unintended soundtrack: the persistent hum of nightlife. In a study from Macedonia, for instance, residents experienced noise levels of about 67 decibels in the evening – a consistent background murmur disrupting the peace of homes.
This issue isn’t just about sound; it’s about the voices of those affected. Residents’ complaints about noise pollution have become a chorus in many parts of the world, including the United Kingdom, Hong Kong, and Australia. These complaints highlight a pressing question: How can we maintain the lively spirit of our cities while respecting the need for quiet?
Governments and communities are tuning into this challenge. Their responses, colored by cultural and historical factors, range from strict regulations to innovative solutions. For example, in Hong Kong, efforts to control noise at its source, as detailed in a government booklet, showcase one way of striking a balance.
This is a story of harmony – finding a middle ground where the joyous buzz of pubs and bars coexists with the serene rhythm of residential life. It’s about understanding that in the symphony of city life, every note, from the loudest cheer to the softest whisper, plays a crucial role.
University of Minnesota 75 East River Parkway Minneapolis, MN 55455 United States
Christopher Feist Christopher Milliren Lori Arent Julia B. Ponder Peggy Nelson Edward J. Walsh
Popular version of 3aABb4 – Behavioral responses of bald eagles (Haliaeetus leucocephalus) to acoustic stimuli in a laboratory setting Presented at the 184 ASA Meeting Read the abstract at https://doi.org/10.1121/10.0018607 Please keep in mind that the research described in this Lay Language Paper may not have yet been peer reviewed.
The ultimate goal of this project is to protect eagles by discouraging these charismatic birds from entering the airspace of wind energy facilities. The specific question under consideration centers on whether or not an acoustic cue, a sound, can be used for that purpose, to steer eagles away from harm’s way. Our specific goal in this particular study was to take the next step along our overall research path and determine if behaviors of bald eagles in particular were affected by different sound stimuli in a controlled laboratory environment.
Perhaps to be expected, behavioral responses varied significantly. Some birds explored their immediate airspace avidly, while others exhibited a more restrained set of behavioral responses to sound stimulation.
To get a feeling for the task, consider the reaction of this eagle to a sound stimulus in a quiet laboratory setting .
To collect these data, a bird was placed in a sound-damped room and the experiment was conducted from a control center just outside the exposure space. Birds were videotaped as sounds were delivered to one of two speakers and a group of unbiased judges was asked to determine (1) whether the bird responded to the sound based on its behavior, (2) to qualitatively assess the strength of the response, and (3) to identify the behaviors associated with the response. Twelve sounds were tested and judges were instructed to observe the eagle during a specified time window without knowing which sound, if any, had been played. Spectrograms of the sounds tested are shown in the figure.
By far the most common response was an attempt to localize the sound source based on head turning toward a speaker, although birds also frequently tilted their heads in response to stimuli. Females were slightly more responsive to sound stimuli than males, and not surprisingly, stimuli that elicited a higher number of responses also elicited stronger or more evident responses. Complex and natural sounds, for example, sounds produced by eagles, eaglets and pesky mobbing crow sounds, elicited more and stronger responses than man-made stimuli. Generally, bald eagles were fairly accurate in locating the direction that the sound originated, and, as before, females performed better than males.
The results from this study provide a critical step in an effort to protect eagles as we move away from the use of fossil fuels and rely more on wind power. We come away from this study with a better understanding of the types of sound signals that elicit more and stronger responses in bald eagles, and with the confidence that we will be able to objectively assess behavioral responses in more natural settings. We now know what these magnificent birds can hear, and we know that certain sound stimuli are more effective than others in evoking behavioral responses, taking us one step closer to our ultimate goal, to save bald eagles from undesirable outcomes and to give wind facility developers the tools needed to manage their facilities in an even more eco-friendly manner.
NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA, 91109, United States
Daniel C. Bowman2, Emalee Hough3, Zach Yap3, John D. Wilding4, Jamey Jacob3, Brian Elbing3, Léo Martire1, Attila Komjathy1, Michael T. Pauken1, James A. Cutts1, Jennifer M. Jackson4, Raphaël F. Garcia5, and David Mimoun5
1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA
2. Sandia National Laboratories, Albuquerque, New Mexico, USA
3. Oklahoma State University, Stillwater, OK, USA
4. Seismological Laboratory, California Institute of Technology, Pasadena, CA, USA
5. Institut Supérieur de l’Aéronautique et de l’Espace (ISAE-SUPAERO), Toulouse, France
Popular version of 4aPAa1 – Development of Balloon-Based Seismology for Venus through Earth-Analog Experiments and Simulations
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018837
Venus has often been described as a “hellscape” and deservedly so – the surface of Venus simultaneously scorches and crushes spacecraft that land on it with temperatures exceeding 460 degrees Celsius (~850 F) and atmospheric pressure exceeding 90 atmospheres. While the conditions on the surface of Venus are extreme, the temperature and pressure drop dramatically with altitude. At about 50-60 km above the surface, temperature (-10-70 C) and pressure (~0.2-1 atmosphere) resemble that on Earth. At this altitude, the challenge of surviving clouds of sulfuric acid is more manageable than that of surviving the simultaneous squeeze and scorch at the surface. This is evidenced by the fact that the two VeGa balloons floated in the atmosphere of Venus by the Soviet Union in 1985 transmitted data for approximately 48 hours (and presumably survived for much longer) compared to 2 hours and 7 minutes, which is the longest any spacecraft landed on the surface has survived. A new generation of Venus balloons is now being designed that can last over 100 days and can change their altitude to navigate different layers of Venus’ atmosphere. Our research focuses on developing technology to detect signatures of volcanic eruptions and “venusquakes” from balloons in the Venus clouds. Doing so allows us to quantify the level of ongoing activity on Venus, and associate this activity with maps of the surface, which in turn allows us to study the planet’s interior from high above the surface. Conducting this experiment from a balloon floating at an altitude of 50-60 km above the surface of Venus provides a significantly extended observation period, surpassing the lifespan of any spacecraft landed on the surface with current technology.
We propose to utilize low-frequency sound waves known as infrasound to detect and characterize Venus quakes and volcanic activity. These waves are generated due to coupling between the ground and the atmosphere of the planet – when the ground moves, it acts like a drum that produces weak infrasound waves in the atmosphere, which can then be detected by pressure sensors deployed from balloons as shown in figure 1. On Venus, the process of conversion from ground motion to infrasound is up to 60 times more efficient than Earth.
Figure 1: Infrasound is generated when the atmosphere reverberates in response to the motion of the ground and can be detected on balloons. Infrasound can travel directly from the site of the event to the balloon (epicentral) or be generated by seismic waves as they pass underneath the balloon and travel vertically upward (surface wave infrasound).
We are developing this technique by first demonstrating that earthquakes and volcanic eruptions on Earth can be detected by instruments suspended from balloons. These data also allow us to validate our simulation tools and generate estimates for what such signals may look like on Venus. In flight experiments over the last few years, not just several earthquakes of varying magnitudes and volcanic eruptions, but also other Venus-relevant phenomena such as lightning and mountain waves have been detected from balloons as shown in figure 2.
Figure 2: Venus-relevant events on Earth detected on high-altitude balloons using infrasound. Pressure waves from the originating event travel to the balloon and are recorded by barometers suspended from the balloon.
In the next phase of the project, we will generate a catalog of analogous signals on Venus and develop signal identification tools that can autonomously identify signals of interest on a Venus flight.
Copyright 2023, all rights reserved. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).
NUWC Division Newport, NAVSEA, Newport, RI, 02841, United States
Dr. Lauren A. Freeman, Dr. Daniel Duane, Dr. Ian Rooney from NUWC Division Newport and
Dr. Simon E. Freeman from ARPA-E
Popular version of 1aAB1 – Passive Acoustic Monitoring of Biological Soundscapes in a Changing Climate
Presented at the 184 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0018023
Climate change is impacting our oceans and marine ecosystems across the globe. Passive acoustic monitoring of marine ecosystems has been shown to provide a window into the heartbeat of an ecosystem, its relative health, and even information such as how many whales or fish are present in a given day or month. By studying marine soundscapes, we collate all of the ambient noise at an underwater location and attribute parts of the soundscape to wind and waves, to boats, and to different types of biology. Long term biological soundscape studies allow us to track changes in ecosystems with a single, small, instrument called a hydrophone. I’ve been studying coral reef soundscapes for nearly a decade now, and am starting to have time series long enough to begin to see how climate change affects soundscapes. Some of the most immediate and pronounced impacts of climate change on shallow ocean soundscapes are evident in varying levels of ambient biological sound. We found a ubiquitous trend at research sites in both the tropical Pacific (Hawaii) and sub-tropical Atlantic (Bermuda) that warmer water tends to be associated with higher ambient noise levels. Different frequency bands provide information about different ecological processes (such as fish calls, invertebrate activity, and algal photosynthesis). The response of each of these processes to temperature changes is not uniform, however each type of ambient noise increases in warmer water. At some point, ocean warming and acidification will fundamentally change the ecological structure of a shallow water environment. This would also be reflected in a fundamentally different soundscape, as described by peak frequencies and sound intensity. While I have not monitored the phase shift of an ecosystem at a single site, I have documented and shown that healthy coral reefs with high levels of parrotfish and reef fish have fundamentally different soundscapes, as reflected in their acoustic signature at different frequency bands, than coral reefs that are degraded and overgrown with fleshy macroalgae. This suggests that long term soundscape monitoring could also track these ecological phase shifts under climate stress and other impacts to marine ecosystems such as overfishing.
A healthy coral reef research site in Hawaii with vibrant corals, many reef fish, and copious nooks and crannies for marine invertebrates to make their homes.
Soundscape segmented into three frequency bands capturing fish vocalizations (blue), parrotfish scrapes (red), and invertebrate clicks along with algal photosynthesis bubbles (yellow). All features show an increase in ambient noise level (PSD, y-axis) with increasing ocean temperature at each site studied in Hawaii.
Figure 1: Pressure-stiffness playability map. The black regions correspond to parameter combinations that generate sound.
Figure 1: Pressure-stiffness playability map. The black regions correspond to parameter combinations that generate sound.
Figure 1 – the North Boma area
Figure 2 – MFA results show that retroflex and non-retroflex nasals behave very differently in North Boma
Image courtesy of Kvikoo, Singapore
Figure 1: Infrasound is generated when the atmosphere reverberates in response to the motion of the ground and can be detected on balloons. Infrasound can travel directly from the site of the event to the balloon (epicentral) or be generated by seismic waves as they pass underneath the balloon and travel vertically upward (surface wave infrasound).
Figure 2: Venus-relevant events on Earth detected on high-altitude balloons using infrasound. Pressure waves from the originating event travel to the balloon and are recorded by barometers suspended from the balloon.
A healthy coral reef research site in Hawaii with vibrant corals, many reef fish, and copious nooks and crannies for marine invertebrates to make their homes.
Soundscape segmented into three frequency bands capturing fish vocalizations (blue), parrotfish scrapes (red), and invertebrate clicks along with algal photosynthesis bubbles (yellow). All features show an increase in ambient noise level (PSD, y-axis) with increasing ocean temperature at each site studied in Hawaii.