William J Davies

• PhD
• Professor at University of Salford

Categorisation is a fundamental cognitive process that plays a central role in everyday behaviour and action. Whereas previous studies have investigated the categorisation of isolated everyday sounds, this paper presents an experiment to investigate the cognitive categorisation of everyday sounds within their original context. A group of eighteen e...

Object-based audio presents the opportunity to optimize audio reproduction for different listening scenarios. Vector base amplitude panning (VBAP) is typically used to render object-based scenes. Optimizing this process based on knowledge of the perception and practices of experts could result in significant improvements to the end user's listening...

Five evidence-based taxonomies of everyday sounds frequently reported in the soundscape literature have been generated. An online sorting and category-labeling method that elicits rather than prescribes descriptive words was used. A total of N = 242 participants took part. The main categories of the soundscape taxonomy were people, nature, and manm...

We investigated human response to soundscapes using a continuous second-by-second rating of soundscapes and a more conventional overall rating of each sample at the end of each audition. In this work, our primary aim was to explore what continuous ratings tell us about soundscape perception. Our secondary aim was to understand how pupil dilation re...

Background: Hospitals provide treatment to improve patient health and well-being but the characteristics of the care environment receive little attention. Excessive noise at night has a negative impact on in-patient health through disturbed sleep. To address this hospital staff must measure night-time environmental noise levels. Therefore, an unde...

Purpose of review This study aims to investigate anthropogenic noise impact on avian species by means of a systematic review of literature. Recent findings Based on previous anthropogenic noise impact frameworks, it was possible to: clarify the impacts of noise on birds; optimise the existing frameworks with findings produced over 44 years; recate...

The study of the perceived affective qualities (PAQs) in soundscape assessments have increased in recent years, with methods varying from in-situ to laboratory. Through technological advances, virtual reality (VR) has facilitated evaluations of multiple locations in the same experiment. In this paper, VR reproductions of different urban sites were...

Purpose of Review This review collates and analyses data on noise exposure of birds in relation to avian hearing system performance. It provides new insights into the mechanistic pathways of anthropogenic noise impact on avian species. Recent Findings Noise impacts both humans and wildlife. Birds are of conservation concern, given the recent repor...

Executive summary 1. The aim of this report is to review whether A-Weighting accurately represents the hearing of the whole UK population, to explore the consequences if it does not, and to make recommendations for future research to address the problems identified. 2. The approach taken was to first research the construction of A-Weighting from...

In recent years, several studies have shown how anthropogenic noise impacts wildlife. The methodologies used to quantify noise appear to influence data reliability and subsequent findings. Therefore, it is appropriate to review the robustness of acoustic measurement procedures to understand the extent to which studies can be relied upon. In 2023, t...

The Habitats project integrates research in the fields of ecological impacts and environmental noise to facilitate development of management tools and processes needed for sustainable development. This conference paper summarises the content and outcomes of a workshop at the University of Salford on 15th December 2022, focused on the development of...

Since the definition of the Environmental Noise Directive 2002/49/EC, various tools, reports, and action plans have been developed to assess and improve the sonic environment according to human perception and well-being. Few methodologies and reports consider the measurement of the impacts of anthropogenic sounds on wildlife at a European level. No...

Over the recent years, it became more evident in soundscape studies realised in urban parks the importance of natural sound sources as a restorative resource for human health and well-being. This study investigates psychoacoustic and bioacoustics patterns of natural sound sources in urban soundscapes to understand and enhance restorative environmen...

Autism is a lifelong neurodevelopmental condition diagnosed by differences in social interaction, communication, and imagination. Most autistic people also experience atypical sensory processing (e.g., a heightened sensitivity to sound or texture). The literature includes evidence of autistic hearing differences including hyperacusis, enhanced pitc...

This paper presents results from the Manchester Soundscape Experiment Online 2020. It consisted of a virtual reality (VR) experiment online where participants rated 12 different scenarios with questions. The selected locations were Piccadilly Gardens, Market Street, Peel Park, and a bus stop. Each site was visited and recorded with a 360 camera and...

The objective of the Habitats project is to integrate research in the fields of ecological impacts and of environmental noise to develop management tools and processes to enable sustainable development. Human society is facing a huge global challenge. Rapid population expansion and economic development against the backdrop of climate and biodiversi...

In recent years, it became more evident that the physical environment cannot characterize the sonic built environment without considering subjects’ opinions, preferences, and expectations while using the urban space. Due to these reasons, an increase of the investigations on soundscape studies related to cognitive aspects such as the emotional dime...

Over the last ten years, several researchers investigated the emotional aspect of soundscape perception responses. Some essential findings helped to highlight relevant dimensions of the emotional content of soundscape perceptual responses. Initially, Axelsson et al. (2010) verified the emotional dimensions with the Circumplex model of affect develo...

This paper reports an attempt to use soundscape assessment tools to investigate the impact of industrial noise in a quiet area. The conservation of quiet areas is encouraged due to their positive effects on health. However, typically the assessment of industrial noise neither promotes the conservation of quiet areas nor quantifies the impact on the...

Given the restrictions due to the global pandemic, online listening tests become an alternative way of collecting data. In adaptation, the Manchester Soundscape Experiment Online had a contribution of 158 participants between the months of August to November 2020. The objective was to investigate whether different soundscapes and crowd densities mo...

Sounds in urban areas have traditionally been treated as an annoyance for which noise control solutions aim mostly at reducing sound levels. However, recent studies demonstrate that soundscapes could also enhance the quality of life and become a resource for urban planning. This work aims to investigate how human presence in urban settings can modu...

Pupil dilation has previously been shown to be a useful involuntary marker of listening effort. An inverse relationship between pupil diameter and signal to noise ratio has been shown when speech is energetically masked by noise. The work reported here aimed to investigate whether this relationship also holds for informational masking. Informationa...

Although audio is often reproduced with a visual counterpart, the audio technology for these systems is often researched and evaluated in isolation from the visual component. Previous research indicates that the auditory and visual modalities are not processed separately by the brain. For example, visual stimuli can influence ratings of audio quali...

With the purpose of assisting developments in urban soundscape design, the present research investigates how soundscapes can influence emotions and behaviours in public spaces aiming to find healthy reactions to “exciting” sonic environments. In the current study, an “exciting” soundscape represents sounds with high levels of pleasantness and event...

Auditory salience describes the extent to which sounds attract the listener’s attention. So far, there have not been any published studies testing if the location of sound relative to the listener influences its salience. In fact, not many experiments in general test auditory attention in a fully spatialised setting, with sounds in front and behind...

Acoustic Event Detection (AED) is an important task of machine listening which, in recent years, has been addressed using common machine learning methods like Non-negative Matrix Factorization (NMF) or deep learning. However, most of these approaches do not take into consideration the way that human auditory system detects salient sounds. In this w...

Humans are able to identify a large number of environmental sounds and categorise them according to high-level semantic categories, e.g. urban sounds or music. They are also capable of generalising from past experience to new sounds when applying these categories. In this paper we report on the creation of a data set that is structured according to...

Recent technological advances in object-based broadcasting present the opportunity to improve broadcast accessibility, particularly for the 11 million people in the UK with hearing impairment. Taking advantage of this opportunity is important given the key social role television plays, especially for older people. To best exploit this opportunity,...

Object-based audio can be used to customize, personalize, and optimize audio reproduction depending on the specific listening scenario. To investigate and exploit the benefits of object-based audio, a framework for intelligent metadata adaptation was developed. The framework uses detailed semantic metadata that describes the audio objects, the loud...

The challenge of installing and setting up dedicated spatial audio systems can make it difficult to deliver immersive listening experiences to the general public. However, the proliferation of smart mobile devices and the rise of the Internet of Things mean that there are increasing numbers of connected devices capable of producing audio in the hom...

The present work involved a sound-sorting and category-labelling task that elicits rather than prescribes words used to describe sounds, allowing categorization strategies to emerge spontaneously and the interpretation of the principal dimensions of categorization using the generated descriptive words. Previous soundscape work suggests that ‘everyd...

Hearing loss affects one in six people in the United Kingdom and, given an aging population, this is figure is increasing. Numerous studies highlight that for individuals with hearing loss improvements in the intelligibility of television sound is required. Recent developments in object-based broadcasting show the potential to deliver such improvem...

Zoo animals are daily exposed to large crowds of visitors and the sounds produced by them, which are proven to have a significant contribution to noise levels in this venue. However, soundscapes in zoos are much more complex than just visitor sounds, and the impact of different sources of sound has not been properly explored. In humans, the stressf...

Previous studies have shown relationships between sound objects by grouping general sound objects according to how people perceive them (i.e. positively or negatively), but not according to how specific sound objects and their interaction affect soundscape perception. Soundscape composition using an acoustic environment simulator is introduced to a...

In everyday life, speech is often accompanied by a situation-specific acoustic cue; a hungry bark as you ask ‘Has anyone fed the dog?’. This paper investigates the effect such cues have on speech intelligibility in noise and evaluates their interaction with the established effect of situation-specific semantic cues. This work is motivated by the intr...

An acoustic environment simulator is a system that facilitates acoustic environment composition by controlling the parameters of sound objects (both background and sound events), allowing the user to compose and compare soundscapes against their expectations. By using the acoustic environment simulator, data regarding parameters of sound objects, s...

A method has been developed that utilizes a sound-sorting and labeling procedure, with correspondence analysis of participant-generated descriptive terms, to elicit perceptual categories of sound. Unlike many other methods for identifying perceptual categories, this approach allows for the interpretation of participant categorization without the re...

No PDF available ABSTRACT Hitherto, not many studies have dealt with spatial auditory saliency. Auditory attention studies concerned with spatial aspects generally concentrate on top-down selective or divided attention, e.g., where subjects are asked to attend to one source at a specific location whilst being distracted with sources from different...

The traditional paradigm for the assessment of audio quality is that of a listener positioned in the geometric center of a standardized loudspeaker setup, fully attending to the reproduced sound scene. However, this is not how listeners generally interact with audio technology. Audio is consumed in a variety of environments and situations, over dev...

Musicians have been reported to show significant inter-Individual differences in elementary hearing functions, sound perception mode, musical instrument preference, performance style, as well as more complex musical abilities like absolute- and relative pitch perception, and auditory imagery. However, it remains unexplored how individual elementary...

As an acoustic scene becomes more complex listeners increasingly rely on complementary intelligibility cues, such as context and language structure, to understand speech. Despite the role salient non-speech audio elements, like sound effects, play in establishing context, approaches to make broadcast audio more intelligible have primarily assumed t...

An organizing account of everyday sounds could greatly simplify the management of audio data. The job of an audio database manager will typically involve assigning a combination of textual descriptors to audio data, and perhaps allocation to a predefined category. Retrieval is likely achieved by matching the descriptor to keyword search terms or by...

The aim of this work was to investigate the perception of soundscape reproduced by an ambisonic reproduction system on a horizontal plane, how the experience of space affected the perception of soundscape reproduction, and how the sound level adjustment on soundscape reproduction affected the perception of soundscape compared with actual conditions...

Soundscape perception based on soundscape dimensions was investigated using a soundscape simulator. A soundscape simulator is a system to design a soundscape by controlling the parameters of sound objects (both background and event sound), allowing the participants to compose a soundscape according to their expectation. In this study, the participa...

This paper presents a series of experiments to determine a categorization framework for broadcast audio objects. Object-based audio is becoming an evermore important paradigm for the representation of complex sound scenes. However, there is a lack of knowledge regarding object level perception and cognitive processing of complex broadcast audio sce...

The fields of soundscapes, music cognition and audio quality have many similarities. Researchers in these areas are all dealing with perception and cognition of complex acoustic scenes. To date, there has been little cross-fertilisation between them. This paper examines some key concepts and results from soundscapes, music and audio. It is shown th...

This paper explores how expectations of a place and its soundscape can affect our perception of that soundscape. Previous soundscape research has included expectation as one possible element of the context in which soundscape evaluation takes place. This work aimed to focus on expectation and unpack it to improve understanding of its different comp...

This investigation assessed a number of 2D and 3D surround systems focusing on the attribute envelopment‟ to determine if surround systems with height significantly enhance the perception of envelopment over current 2D systems. To assess each of the systems an objective and subjective method was used. The objective method consisted of measuring the...

The smallest change in reverberation time that can be perceived in a concert hall has been measured. Five existing halls with average reverberation times varying between 0.89 and 2.3 s were simulated in detail with Bose room acoustic modelling software. The computer models were verified against acoustic measurements in the real halls. The models we...

The aims of this work were to investigate (i) whether soundscape perceptual dimensions are correctly reproduced by ambisonic loudspeaker playback, (ii) whether soundscape dimensional analysis is robust to changes of location and from the field to laboratory playback, and (iii) whether a simple soundscape synthesis can be used to interactively desig...

This paper takes an overall view of findings from the Positive Soundscape Project, a large inter-disciplinary soundscapes study. Qualitative fieldwork (soundwalks and focus groups) have found that soundscape perception is influenced by cognitive effects such as the meaning of a soundscape and its components, and how information is conveyed by a sou...

Increasing the order of ambisonic reproduction allows 3D sound fields to be reconstructed with improved resolution and enhanced localisation, at the expense of higher channel counts, increased broadcast bandwidth, and increased storage requirements. Due to the resolution of human hearing it is possible that lowerorder reproduction is sufficient for...

Current 2D surround systems have benefitted from years of research which has helped identify attributes related to listener preference. Now with high definition visuals, 3D cinema, there is a need to further develop spatial audio systems. One method would be with the addition of height channels, however it is unknown how this will impact on the lis...

In small rooms, low-frequency modes have a degrading influence on the quality of the bass components of music. Using objective measures to correct these modes often fails because they do not correspond to the subjective experience of listeners. This research begins with a procedure that elicits a compact set of four verbal descriptors from subjects...

I am conducting a Grounded Theory approach to measuring opinions of urban soundscapes. This approach makes it possible to focus on the soundscapes experienced by an individual in their daily life, instead of focussing on the soundscape of a specific location. Participants are given a small portable recording device and asked to keep a sound diary f...

Ambisonics allows the reproduction of 3D sound-fields. Higher-order Ambisonics provides improved resolution, and the promise of enhanced localisation at the expense of higher channel counts, and increased broadcast bandwidth, and storage requirements. Due to the resolution of human hearing it is possible that lower-order reproduction is sufficient...

The aim of this work was to investigate the validity of laboratory soundscape reproduction and the robustness of soundscape dimensional analysis. The soundscapes in four urban locations in Manchester (UK) were recorded with a soundfield microphone. The soundscapes were reproduced through an ambisonic 3D loudspeaker system in a semi-anechoic chamber...

This chapter gives an overview of what shapes the acoustic signals that arrive at the ear. It is structured as an account of the journey of a sound wave, from first generation, then propagation outdoors, followed by transmission into a building and indoor reverberation to its final reception, perception, and assessment. In doing so, I seek to shed...

Current policy on environmental sound is largely based on noise control. There is considerable interest in exploiting the soundscape concept to provide a more sophisticated way of managing our acoustic environment. For this to happen, a tool for assessing soundscape quality is needed. This paper reports on an exploratory attempt to define a soundsc...

More than one factor analysis of soundscape perception has concluded that speech communication is a significant contributor to the overall perceived quality of urban soundscapes. While not everything that is perceptually significant in real soundscapes can be quantified it seems likely that speech intelligibility can. There is a large literature on...

This paper discusses how expectation and experience form a contributory factor in the perception of soundscapes. The research used fieldwork carried out in London and Manchester, and also a soundscape simulator in a laboratory. Through the use of an enhanced version of soundwalking, respondents are led on a walk around an urban space focusing on th...

This paper discusses the development of an interactive soundscape simulator, enabling users to manipulate a series of parameters to investigate if there is group correlation between factors such as source selection, positioning and level. The basis of the simulator stems from fieldwork and recordings carried out in London and Manchester. Through th...

This paper takes an overall view of ongoing findings from the Positive Soundscape Project, a large inter-disciplinary soundscapes study which is nearing completion. Qualitative fieldwork (soundwalks and focus groups) and lab-based listening tests have revealed that two key dimensions of the emotional response are calmness and vibrancy. In the lab t...

The concept of soundscapes is an established theme in acoustics research, most notably in the areas of environmental noise, noise control and psychoacoustics. However, many disciplines outside of traditional acoustics have recently worked together to confront epistemological assumptions regarding the place of soundscapes in an urban planning con...

The Positive Soundscape Project is a large multi-disciplinary project investigating the perception of soundscapes. Recent findings indicate that speech communication is a principal factor in users’ perceptions of urban soundscapes. The project has therefore explored how this factor might be quantified. This paper reports on an attempt to use speech...

1 The aim of this review was to investigate existing research into soundscape concepts and to produce recommendations for future research into the practical identification, management and enhancement of soundscapes in urban areas. 2 Existing research on soundscapes was investigated using four methods: i. a survey of more than 500 papers in the acad...

People's assessments of urban soundscapes are dependent upon many factors. For example, perceptions of a soundscape may depend on the activity that the listener is doing and their associated listening state at the time. Temporal variations (daily, weekly, seasonal) can also affect perceptions of the soundscape, as can the type and usage of urban sp...

Soundwalking is a practice that was devised by R. Murray Schafer, when he established the World Soundscape Project at Simon Fraser University during the late 1960s and early 1970s. It is an empirical method for identifying a soundscape and components of a soundscape in various locations. In the EPSRC-funded Positive Soundscapes Project (Davies e...

The Positive Soundscapes Project is an interdisciplinary investigation of soundscape perception [1]. The project seeks to develop a rounded view of human perception of soundscapes by drawing together methods from the disciplines of engineering sound quality [2], acoustics, psychoacoustics, physiology [3], as well as sound art, acoustic ecology a...

In an attempt to understand the effect of sounds on physiological measurements, along the positive (pleasant) - negative (unpleasant) subjective dimension, 51 subjects (26 male) listened to 13 sounds in clips of 8s interspersed with 16s of silence while their heart rate, respiratory rate and skin conductance were measured and they recorded the subj...

The Positive Soundscape Project is a multi-disciplinary investigation of soundscape perception which started in October 2006. This paper communicates the aims and design of the project and discusses some early results. The project seeks to develop a rounded view of human perception of soundscapes by combining methods from several disciplines. This...

An investigation into the measurement of the thresholds of detection of modal Q factors in rooms at low frequency is measured. Key features of the approach taken include the use of music rather than test tones or noise as program material, and the manipulation of damping conditions for a range of modes over a broad low-frequency bandwidth as oppose...

A method of objectively measuring the spatial capabilities of multichannel sound systems has been investigated. The method involved the comparison of interaural cross correlation (IACC) measurements taken in a concert hall to IACC measurements taken in reproduced versions of the same concert hall. The type of reproduction system was varied and an i...

The subjective significance of two general types of metrics used to describe the "quality" of a room based on its aspect ratio are compared. Tests were carried out to evaluate differences between three virtual rooms that score extreme classifications in each of the metrics. The results of the tests indicate that room aspect ratios do have sonic eff...

This paper investigates a connection between perceptions of indoor and outdoor soundscapes. The word susurration is used in non-scientific writing to describe sounds such as wind in trees and rushing water. It is hypothesised that these sounds give rise to a sensation of envelopment in a similar manner to the indoor susurration of reverberated spee...