Traditional expertise on public spaces advocates for a reduction in sound level to improve sound quality in urban spaces. Beside noise masking used in some indoor contexts, the role of added sound and particularly sound art in the public domain is less understood. Over the course of the summer and early fall of 2018, Montreal carried out a public space-making project in three consecutive configurations of 30 or more days each. During 2 of these configurations, a custom audio installation involving 4 outdoor, public speakers was installed by Audiotopie, a local audio design collective that specializes in sound installations. Each audio installation was on site for a minimum of 10 days. We measured the effect of the sound installation on users' experience using questionnaires that included the Swedish Soundscape Quality Protocol, person-related (e.g. personality) and situation-related (e.g. activity) variables (N = 329). We observed changes in soundscape evaluations when the sound installations were in place compared to the baseline condition. Specifically, for Configuration 1, the sound installation increased calmness and the ability to take a break and reduced the perceived overall sound level. It should be noted that the effects were observed only in the proximity of the sound installation, where the audio content was clearly audible. For Configuration 2, the installation increased pleasantness and calmness over the whole site, while again reducing the perceived sound level. The results suggest implications for urban design and planning in that sound design can improve perceived sound character, but more importantly for traditional planning purposes, perceived sound level.
