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Vol 42 No 3

CONTENTS

December 2014


ARTICLES: Including Special Issue Part 2: AUDITORY PERCEPTION

Intensity Dynamics and Loudness Change: A Review of Methods and Perceptual Processes
Kirk N. Olsen
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Language Experience Shapes Processing of Pitch Relevant Information in the Human Brainstem and Auditory Cortex: Electrophysiological Evidence
Ananthanarayan Krishnan and Jackson T. Gandour
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Methods for Assessing the Quality of Transmitted Speech and of Speech Communication Services
Friedemann K?ster, Sebastian M?ller, Jan-Niklas Antons, Sebastian Arndt, Dennis Guse and Benjamin Weiss
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Detection of Sharks with the Gemini Imaging Sonar
Miles Parsons, Iain M. Parnum, Kim Allen, Robert D. McCauley and Christine Erbe
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A Matlab tool for the Characterisation Of Recorded Underwater Sound (CHORUS)
Alexander N. Gavrilov, Miles J.G. Parsons
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Comparison of Infrasound Measured at People?s Ears When Walking to that Measured Near Wind Farms
Matthew Stead, Jon Cooper and Tom Evans
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TECHNICAL NOTES

Remote Beehive Monitoring Using Acoustic Signals
Amro Qandour, Iftekhar Ahmad, Daryoush Habibi and Mark Leppard
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Modelling the Interior Sound Field of a Railway Vehicle Using Finite Element Method
WU Di and GE Jianmin
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Constructive Interference of Tonal Infrasound from Synchronised Wind Farm Turbines: Evidence and Implications
Andrew Bell
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Intensity Dynamics and Loudness Change: A Review of Methods and Perceptual Processes

Kirk N. Olsen
The MARCS Institute, University of Western Sydney, Australia This e-mail address is being protected from spambots. You need JavaScript enabled to view it
This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 42, No. 3 pp 159 - 165 (2014)
ABSTRACT: In real-world listening domains such as speech and music, acoustic intensity and perceived loudness are dynamic and continuously changing through time. The percept of loudness change in response to continuous increases (up-ramps) and decreases (down-ramps) of intensity has received ongoing empirical and theoretical interest, the result of which has led to conflicting findings from a range of key paradigms. Therefore, the aim of this brief review is to: (a) describe key paradigms used to measure changes in loudness in response to continuous intensity change; (b) identify methodological issues associated with each paradigm; and (c) discuss the mechanisms proposed to explain differences in loudness change when methodological constraints and response biases are controlled. It is concluded that direct and indirect measures of loudness change reflect two distinct aspects of auditory perception. Specifically, magnitude estimation and continuous loudness paradigms reflect changes in perception associated with a ramp?s direction and magnitude of intensity change, and empirical evidence supports the conclusion that greater loudness change in response to down-ramps relative to up-ramps is the real-time perceptual outcome. On the other hand, retrospective global judgements of loudness change are disproportionally weighted on end-level intensity rather than magnitude of intensity change. However, an up-ramp- specific effect of duration on global loudness change is evident when end-level response bias is controlled, and this may be associated with end-point time-of-arrival responses to real and apparent looming auditory motion.

Language Experience Shapes Processing of Pitch Relevant Information in the Human Brainstem and Auditory Cortex: Electrophysiological Evidence

Ananthanarayan Krishnan, PhD1; Jackson T. Gandour, PhD1
1 Department of Speech Language Hearing Sciences, Purdue University, West Lafayette, IN 47907, USA This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 42, No. 3 pp 166 - 178 (2014)

ABSTRACT: Pitch is a robust perceptual attribute that plays an important role in speech, language, and music. As such, it provides an analytic window to evaluate how neural activity relevant to pitch undergo transformation from early sensory to later cognitive stages of processing in a well coordinated hierarchical network that is subject to experience-dependent plasticity. We review recent evidence of language experience-dependent effects in pitch processing based on comparisons of native vs. nonnative speakers of a tonal language from electrophysiological recordings in the auditory brainstem and auditory cortex. We present evidence that shows enhanced representation of linguistically-relevant pitch dimensions or features at both the brainstem and cortical levels with a stimulus-dependent preferential activation of the right hemisphere in native speakers of a tone language. We argue that neural representation of pitch-relevant information in the brainstem and early sensory level processing in the auditory cortex is shaped by the perceptual salience of domain-specific features. While both stages of processing are shaped by language experience, neural representations are transformed and fundamentally different at each biological level of abstraction. The representation of pitch relevant information in the brainstem is more fine-grained spectrotemporally as it reflects sustained neural phase-locking to pitch relevant periodicities contained in the stimulus. In contrast, the cortical pitch relevant neural activity reflects primarily a series of transient temporal neural events synchronized to certain temporal attributes of the pitch contour. We argue that experience-dependent enhancement of pitch representation for Chinese listeners most likely reflects an interaction between higher-level cognitive processes and early sensory-level processing to improve representations of behaviorally-relevant features that contribute optimally to perception. It is our view that long-term experience shapes this adaptive process wherein the top-down connections provide selective gating of inputs to both cortical and subcortical structures to enhance neural responses to specific behaviorally-relevant attributes of the stimulus. A theoretical framework for a neural network is proposed involving coordination between local, feedforward, and feedback components that can account for experience-dependent enhancement of pitch representations at multiple levels of the auditory pathway. The ability to record brainstem and cortical pitch relevant responses concurrently may provide a new window to evaluate the online interplay between feedback, feedforward, and local intrinsic components in the hierarchical processing of pitch relevant information.

Methods for Assessing the Quality of Transmitted Speech and of Speech Communication Services

Friedemann Ko?ster, Sebastian Mo?ller, Jan-Niklas Antons, Sebastian Arndt, Dennis Guse, Benjamin Weiss Quality and Usability Lab, Telekom Innovation Laboratories, Technische Universita?t Berlin, Berlin, Germany {friedemann.koester, sebastian.moeller, jan-niklas.antons, sebastian.arndt, dennis.guse, benjamin.weiss}@tu-berlin.de

Vol. 42, No. 3 pp 179 - 184 (2014)
ABSTRACT: The quality of transmitted speech is the major indicator for telecommunication providers to classify their services. As a result, the assessment of quality is of high scientific and economic importance, and corresponding methods for assessing the quality of transmitted speech have been in the focus of multiple studies in the past. In this contribution, traditional methods are reviewed, their weaknesses are identified and improvements and extensions are proposed. The presented work covers subjective, diagnostic, instrumental, and physiological methods, as well as possibilities for evaluating long-term quality aspects.

Detection of Sharks with the Gemini Imaging Sonar

Miles J.G. Parsons1, Iain M. Parnum1, Kim Allen2, Robert D. McCauley1 and Christine Erbe1
1 Centre for Marine Science and Technology, Curtin University, Perth, WA, Australia
2 Intellipulse, Perth, Western Australia

Vol. 42, No. 3 pp 185 - 189 (2014)
ABSTRACT: Limiting environmental impacts of marine industrial operations and mitigating hazardous encounters between humans and marine fauna have become increasingly important as anthropogenic activity expands. To this end, significant effort has been made to develop sonar imaging of fauna and to increase detection and identification ranges. A Tritech Gemini imaging sonar was used to observe sharks of 1.4 to 2.7 m length, at ranges from 1 to 50 m, in various water depths ?15 m. Within 5 m, shark shape, length and swimming action were readily discernible. However, as range increased, knowledge of movement patterns was required to discriminate a 'shark-like' object, before the shark became purely an acoustic target at greater ranges, where visual confirmation of the target was necessary for identification. Once the seafloor is ensonified by the acoustic beam, seafloor backscatter can dominate the image and mask shark detection. The results presented concur with other active acoustic detection studies that, for a given frequency and noise level, maximum detection and identification ranges are reliant on system source level, beam pattern, bathymetry, and target size and acoustic reflectivity.

A Matlab tool for the Characterisation Of Recorded Underwater Sound (CHORUS)

Alexander N. Gavrilov1, Miles J.G. Parsons1
1 Centre for Marine Science and Technology, Curtin University, GPO Box U1987, Perth, WA 6845, Australia This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 42, No. 3 pp 190 - 193 (2014)
ABSTRACT: The advent of low-cost, high-quality underwater sound recording systems has greatly increased the acquisition of large (multi-GB) acoustic datasets that can span from hours to several months in length. The task of scrutinizing such datasets to detect points of interest can be laborious, thus the ability to view large portions of the dataset in a single screen, or apply a level of automation to find or select individual sounds is required. A toolbox that can be continually revised, the user- friendly ?Characterisation Of Recorded Underwater Sound? (CHORUS) Matlab graphic user interface, was designed for processing such datasets, isolating signals, quantifying calibrated received levels and visually teasing out long and short- term variations in the noise spectrum. A function to automatically detect, count and measure particular signals (e.g. blue whale sounds) is integrated in the toolbox, with the ability to include categorised calls of other marine fauna in the future. Sunrise and sunset times can be displayed in long-term average spectrograms of sea noise to reveal diurnal cycles in the vocal activity of marine fauna. A number of example studies are discussed where the toolbox has been used for analysing biological, natural physical and anthropogenic sounds.

Comparison of Infrasound Measured at People?s Ears When Walking to that Measured Near Wind Farms

Matthew Stead1, Jon Cooper1 and Tom Evans1
1 Resonate Acoustics, 97 Carrington Street, Adelaide, SA 5000, Australia This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 42, No. 3 pp 197 - 203 (2014)

ABSTRACT: Infrasound is observed in all environments at varying levels and is generated by a range of natural and anthropogenic sources. Some studies have suggested that modern wind turbines can generate a relatively low level of measurable noise at frequencies corresponding to the blade pass frequency of turbines. People walk at a variety of speeds, with typical walking frequencies similar to the blade passing frequency of modern commercial wind turbines. Measurements have been conducted of the levels of infrasound generated at the human ear when walking and compared to measured levels near wind farms. The measured level of infrasound generated at the ear at blade pass frequency when people walk can be considerably higher than the level near wind farms. In both cases, measured levels were significantly below the audibility threshold for very low frequency noise.

 

Newsflash

PROPOSED INTERNATIONAL YEAR OF SOUND 2019

Let's make 2019 the International Year of Sound!

Click here to see draft prospectus. Suggestions for major activities that would be truly international to strengthen the application are welcomed.

 

ACOUSTICS 2017

Perth, Western Australia 19-22 November 2017