The influence of preconceptions on perceived sound reduction by environmental noise barriers

Abstract

The paper presents research that answers three main questions: (1) Do preconceptions held about the constituent materials of an environmental noise barrier affect how people perceive the barrier will perform at attenuating noise? (2) Does aesthetic preference influence the perception of how a barrier will perform? (3) Are barriers, which are deemed more aesthetically pleasing, more likely to be perceived as better noise attenuators? In a virtual reality setting with film to improve the contextual realism of the intersensory interaction test, participants were required to compare the perceived effectiveness of five standard 'in-situ' noise barriers, including concrete, timber, metal, transparent acrylic and a vegetative screen. The audio stimulus was held at a constant sound pressure level (SPL), whilst the visual stimulus changed, as the influential factor. As the noise levels projected during the study were held constant, it was possible to attribute the participant's perception of noise attenuation by the barriers, to preconceptions of how the varying barrier material would attenuate noise.There was also an inverse correlation between aesthetics and perception of how a noise barrier would perform. The transparent and deciduous vegetation barriers, judged most aesthetically pleasing, were judged as the least effective at attenuating noise.

Using Virtual Reality for assessing the role of noise in the audio-visual design of an urban public space

“…The visual perception of traffic was shown to have a significant influence on perceived noise, increasing the average ratings of noisiness where the degree of visual screening was higher (Watts, Chinn, & Godfrey, 1999). Perceived loudness and noise annoyance was found to be lower for transparent noise barriers than for opaque barriers (Joynt & Kang, 2010;Maffei, Masullo, Aletta, & Di Gabriele, 2013). Certain sounds like traffic noise and especially bird song are rated more negatively the more urban the visual setting is (Viollon, Lavandier, & Drake, 2002).…”

“…Auditory perception improves when accompanied by visuals cues, and similarly, sounds can direct attention to related visual elements (Carles, Barrio, & De Lucio, 1999;Boadbent, 1958;Hong & Jeon, 2014;Joynt & Kang, 2010). The effects of non-auditory factors on soundscape perception has been investigated concluding that urban soundscape is dominated by acoustic comfort, visual images and day lighting (Jeon, Lee, Hong, & Cabrera, 2011).…”

The development of highway nuisance perception

“…Banjung et al, 2003). Joynt and Kang (2010) argued that transparent and vegetative barriers are regarded as more pleasant, but this is not reflected by lower nuisance perception. The type of barrier and the residents' engagement in the design of barriers were also found to be important in this respect (Joynt, 2005;Nederveen 2007).…”

Combined acoustical and visual performance of noise barriers in mitigating the environmental impact of motorways

“…It seems though that 5 m transparent barrier was the least efficient barriers in most scenarios. This might be partly explained by the result found in Joynt & Kang (2010) that transparent barrier was perceived as less efficient than opaque barriers in noise reduction, and partly be explained by that while offering the same or higher noise reduction, transparent barrier reduced nearly no visual impact caused by moving traffic.…”

“…While participants rated the willow barrier more attractive than the metal one, similar perceived noisiness behind the two barriers was reported. Joynt & Kang (2010) conducted a more dedicated and detailed study on the effect of barrier aesthetics. The study compared perceived effectiveness of four motorway noise barriers and a deciduous hedgerow in a laboratory experiment.…”