Perception Of Sound Environment Research Articles

How does visual context of urban open spaces drive soundscape pleasantness and eventfulness: a laboratory experiment using a higher order Ambisonics speaker system and immersive virtual reality

Perception of sound environments is influenced by the context we experience them in. A big portion of the contextual information comes from the visual domain, including our understanding of what a place is but also from its visual features. A laboratory study combining questionnaire responses and eye-tracking tools was designed to investigate if the soundscape outcomes and participants' behaviour inside the simulation can be explained by the perceptual outcomes defined by visual information. 360 degree videos and First Order Ambisonics audio recordings of 27 different urban open spaces taken from the International Soundscape Database were used as the stimuli delivered via a Virtual Reality Head-Mounted Display and a Higher Order Ambisonics speaker array, while a neutral grey environment without sounds being reproduced represented the baseline scenario. A questionnaire tool was deployed within the IVR simulation to collect participants' responses describing their perception of the reproduced environments corresponding to the circumplex model featured in the Method A of the ISO/TS 12913-2. The results revealed a good coverage of the two-dimensional perceptual circumplex space and significant differences between perceptual outcomes driven by sound and those driven by visual stimuli.

Improving the sound environment and preventing risky practices for youth

Noise environment to which young children are subjected in their daily lives can be experienced as annoying and their listening practices with headphones are also increasingly early. During our noise prevention campaigns aimed at elementary school, a questionnaire is proposed before the prevention session to find out their perception of sound environment and their listening practices in terms of headphones or earphones and a second questionnaire during the second session aims to evaluate the knowledge acquired during the first session and the prevention tools tested. The aim is to better understand their perception of the sound environment in order to adapt prevention messages to their practices and to improve the quality of the sound environment of young children. The results (3541 pupils from second to fifth grade) show that young children suffer more from noise at school and in their leisure time than their elders. listening practices which are hazardous for hearing increase with age. The prevention campaigns conducted by the CidB have taken these results into account and thus provide young students with appropriate recommendations for improving the noise environment in the classroom and to protect themselves from high noise levels at leisure.

Lockdown during COVID-19 pandemic: impact on road traffic noise and on the perception of sound environment in France

Abstract Acoucité¹, centre of expertise in environmental acoustics and observatory of the sound environment, has investigated the changes in sound environment and its perception during the French lockdown period. The approach adopted is multidimensional, since it combines long-term acoustic measurements, large area noise mapping, as well as the study of sound perception self-reported by population sample through an on-line structured questionnaire. Data from 21 continuous sound monitoring stations² were analysed for the entire lockdown period in five conurbations in the south of France and compared to typical values in the “normal” situation (before lockdown) in order to quantify the reduction in terms of sound levels. Reductions from 4 dB to 6 dB (Lden) were observed for monitoring stations with highly dominant road noise. These results were used to obtain new Strategic Noise Maps for road noise (corresponding to the lockdown situation) for the conurbations of Lyon and Grenoble. The impact of such reductions in terms of noise exposure of their inhabitants was thus assessed. An estimation of the impact on health effects in comparison with the “normal” situation (Strategic Noise Maps “Round 3 CE-DE-2002”) was also carried out. This estimation considers a scenario where the above level reductions (4 to 6 dB) would take place in the long-term. An on-line perception questionnaire was available during the lockdown period with the aim of gathering information on the way that the changes in sound environment were perceived by people all over France and ended up with more than 3000 respondents. This paper reports the main findings of the study in terms of acoustics and sound perception.

Auditory search asymmetry with pure tone, narrow-band noise, amplitude-modulated tone, and frequency-modulated tone

To examine basic features of sounds used in the perception of sound environment, auditory search tasks seem promising to us. Thus the response time to detect a target sound among distracting sound(s) was measured by three experiments. In the first experiment, pure tones and narrow-band noises (1/12 oct) were used. Either of them was used as a target and the other was used as distractor(s). The number of the distractor was varied from 1 to 6. Each sound was presented from one of seven loudspeakers located on the horizontal plane. In the second and third experiments, pure tones and amplitude-modulated tones, pure tones and frequency-modulated tones, respectively, were used as either a target or distractor(s). Results show that the response time to detect a narrow-band noise, an amplitude-modulated tone, or a frequency-modulated tone among distracting pure tones was hardly affected by the number of the distractors. However, the time required to detect a pure tone increased with the number of distractors. These results indicated that our auditory system utilizes temporal changes in amplitude and frequency of sound as a basic feature for the detection of a sound in a sound environment. Precise experimental results as well as further consideration will be given in the presentation.