ABSTRACT:Sound planning is not often included in the urban design process despite the well-known audio-visual interactions of human perception. A methodology to compare the overall appreciation of future renovation alternatives of urban public spaces using Virtual Reality Technology is proposed. This method is applied to assess the role of noise in the overall appreciation of a walk on a bridge crossing a highway. The auralization is a dynamic 3D surround based on B-format recordings (ambisonics), filtered by means of full-wave numerical calculations obtaining the sound field behind noise barriers along the bridge's edge. Four different styles of visual street design including different noise barrier heights in combination with the 4 corresponding predicted sound fields were evaluated for their pleasantness by 71 normal-hearing participants on 4 separate days. Each day participants experienced all the visual environments with only one soundscape (to elude direct sound comparison) and anything related to sound was not mentioned in the first part of the experiment. Even in this non-focussed context, a statistically significant effect of the sound environment on the overall appreciation was found. In general, the pleasantness increases with traffic noise level reduction, but the visual design has a stronger impact. By mentioning the soundscape while introducing the evaluation, slightly lower (but statistically significantly different) pleasantness ratings were obtained. Instead of increasing noise barrier height, improving the visual design of a lower barrier seems more effective to increase pleasantness.Visual designs including vegetation strongly outperform others. The virtual experience was rated as immersive and realistic.3

People prefer balanced compositions of various types of natural sounds with a focus on bird songs Augmented natural soundscapes improve the environmental noise perception in a park Interactively composed natural soundscapes strongly mask road traffic noise An ICT based approach was presented to improve the perception of urban public spaces

It is increasingly acknowledged by landscape architects and urban planners that the soundscape contributes significantly to the perception of urban public open spaces. Describing and classifying this impact, however, remains a challenge. This article presents a hierarchical method for classification that distinguishes between backgrounded and foregrounded, disruptive and supportive, and finally calming and stimulating soundscapes. This four-class classification is applied to a growing collection of immersive audiovisual recordings of sound environments from around the world that could be explored using virtual reality playback. To validate the proposed methodology, an experiment involving 40 participants and 50 soundscape stimuli collected in urban public open spaces worldwide was conducted. The experiment showed that (1) the virtual reality headset reproduction based on affordable spatial audio with 360degree video recordings was perceived as ecologically valid in terms of realism and immersion; (2) the proposed classification method results in well-separated classes; (3) membership to these classes could be explained by physical parameters, both regarding sound and vision. Moreover, models based on a limited number of acoustical indicators were constructed that could correctly classify a soundscape in each of the four proposed categories, with an accuracy exceeding 88% on an independent dataset.

It has been established that there is an interaction between audition and vision in the appraisal of our living environment, and that this appraisal is influenced by personal factors. Here, we test the hypothesis that audiovisual aptitude influences appraisal of our sonic and visual environment. To measure audiovisual aptitude, an auditory deviant detection experiment was conducted in an ecologically valid and complex context. This experiment allows us to distinguish between accurate and less accurate listeners. Additionally, it allows to distinguish between participants that are easily visually distracted and those who are not. To do so, two previously conducted laboratory experiments were re-analyzed. The first experiment focuses on self-reported noise annoyance in a living room context, whereas the second experiment focuses on the perceived pleasantness of using outdoor public spaces. In the first experiment, the influence of visibility of vegetation on self-reported noise annoyance was modified by audiovisual aptitude. In the second one, it was found that the overall appraisal of walking across a bridge is influenced by audiovisual aptitude, in particular when a visually intrusive noise barrier is used to reduce highway traffic noise levels. We conclude that audiovisual aptitude may affect the appraisal of the living environment.

In recent decades, noise annoyance has been investigated thoroughly as one of the most prominent effects of traffic noise. Still, the influence of visual factors on sound perception is not completely understood. Audiovisual attention focusing and gating are expected to play a role at the perceptual stage. This would also imply the existence of inter-person differences in exposure-effect relationships beyond known factors such as noise sensitivity. To explore these hypotheses, an experiment was designed that combines a newly designed test on audiovisual attention focusing capabilities with a noise annoyance experiment conducted in a mockup living room. The noise annoyance experiment used 16 audiovisual stimuli, which are a combination of 4 window-view video sceneries and 4 sound fragments, to investigate the relative importance of sound source visibility and green elements visibility. In this setting, it was found that (1) sound source visibility, as a functional parameter of the visual setting, has more impact on self-reported noise annoyance than the green element's visibility which describes the quality of the visual; (2) self-reported noise sensitivity remains the strongest personal factor, yet persons being easily distracted by visual elements report significantly lower noise annoyance at the same exposure level; (3) two significant interactions were observed in the prediction of self-reported noise annoyance: (a) noise sensitivity interacts with sound source visibility; (b) vision dominance, as a personal factor, interacts with the visibility of green elements. The interaction between these factors provides additional evidence to support the role of audiovisual attention in the emergence of noise annoyance.