Mental Models of Loudspeaker Directivity

We carry out a study to investigate how naive (non-audio-experts) users understand the concept of sound directivity. This was done in the context of loudspeaker reproduction of sound fields with the purpose being to discover how such acoustical phenomena can best be explained to users. We investigated the mental models of 20 participants via an interview-based approach, in which we asked participants to draw and explain how they understood directivity, only providing them with minimal prior information. The interviews and drawings were analysed and mental models were extracted. Our analysis showed the models could be categorized into three General Mental Model Types (GMMTs): Direction of Sound, Area with Sound, and Sound Waves. These GMMTs were then used to build a 3-level combined model that also contains observations of what each GMMT is suitable for when trying to e.g. explain or illustrate loudspeaker directivity to non-expert users. These guidelines can be useful for designing visual representations to help explain loudspeaker directivity to non-expert users, and could be used for visualising further complex acoustical concepts.