The impact of 3-D sound spatialisation on listeners' understanding of human agency in acousmatic music

Commonly we hear sound without experiencing the associated visual activity to tell us how the sounds were made or from where they originate. In the larger context of electroacoustic music, and more specifically in acousmatic music where causal visual information is removed, it is interesting to investigate how a sense of human agency may be evoked by sound alone. An intuitive starting point would be to assume that the listener identifies source and cause through a sound's close proximity to a known archetype, yet composers often work with materials offering less obvious source clues, while expanding the spatial image over many loudspeakers. New technologies allow us to accurately control the movement of sound in space, and because we understand our own bodies in spatial terms, it is natural to ask how a sound's spatial behaviour influences our listening understanding. This paper investigates two research questions: can listeners identify human agency in 3-D sound, and if so, what are the most salient features involved in this process? Besides being of interest to electroacoustic composers, the topic is also relevant to the audio industry utilising high density loudspeaker arrays in cinema and other spaces where the projection of high resolution spatial imagery is possible.