The effect of vision on the perception of the noise produced by a chiller in a common living environment

Over the years, different noise sources related to community noise and their potential for eliciting noise annoyance have been investigated. Despite being a very common source within the urban realm, there is a current lack of literature on the perception of noise produced by small-medium sized sources like chillers and air-conditioning devices. There are relatively few studies on the influence of audio-visual factors on noise perception for such sources. The main aim of this paper was to investigate the influence of the visibility of a chiller on perceived loudness and self-reported annoyance in an ordinary indoor environment. Furthermore, this research aimed to investigate whether the above mentioned effects persisted in the presence of a cognitive task. To this purpose, two laboratory experiments were performed by means of an Immersive Virtual Reality (IVR) system. Results show that the distance of the chiller influenced the noise perception, while the visibility of the chiller itself does not, assuming that a visual reference context is provided. Regarding the cognitive task, it was found to reduce the mean individual ratings of both the perceived loudness and noise annoyance related to the chiller, signifying that for the investigated sound source characterised by small spectral and temporal variation, it might have inhibited the attentional listening. These findings suggest that there is room for the implementation of recommendations for the design and management of such sources in the increasingly dense built environment.