Towards acoustic indicators for soundscape design

Scientific research on how people perceive, experience or understand the acoustic environment as a whole (i.e., soundscape) is still in development, both with regards to acoustic properties, as well as personality and individual differences. In order to predict how people would perceive an acoustic environment, it is central to identify the underlying acoustic properties of soundscapes. In this study these properties were approached by investigating the visual similarity of colour prints of 50 audio spectrograms (time vs. frequency), representing audio recordings of a variety of acoustic environments. In total, 15 female and 15 male students from the University of Sheffield were recruited to assess the 50 spectrograms by sorting them into groups based on how similar they were perceived to be. A distance matrix, derived from the sorting data, was subjected to a Multidimensional Scaling analysis to map the underlying dimensions of similarity among the spectrograms, which are proposed to represent the underlying acoustic properties of the corresponding acoustic environments. Three dimensions were identified. The first dimension relates to Distinguishable–Indistinguishable sound sources, the second dimension to Background–Foreground sounds, and the third dimension to Intrusive–Smooth sound sources. The results also show that established acoustic parameters are inappropriate as indicators of acoustic environments and that further research is needed in this field.