Song Walker Harmony Space: Embodied Interaction Design for Complex Musical Skills
Music and Human-Computer Interaction
Tonal Harmony is widely considered to be the most technical and complex part of music theory. Consequently harmonic skills can be hard to acquire. Furthermore, experience of the flexible manipulation of harmony in real time generally requires the ability to play an instrument. Even for those with instrumental skills, it can be difficult to gain clear insight into harmonic abstractions. The above state of affairs gives rise to substantial barriers not only for beginners but also for many
... so for many experienced musicians. To address these problems, Harmony Space ) is an interactive digital music system designed to give insight into a wide range of musical tasks in tonal harmony, ranging from performance and composition to analysis. Harmony Space employs a principled set of spatial mappings to offer fluid, precise, intuitive control of harmony. These mappings give rise to sensory-motor and music-theoretic affordances that are hard to obtain in any other way. As a result, harmonic abstractions are rendered amenable to concrete, visible control by simple spatial manipulation. In the language of conceptual metaphor theory, many relationships in tonal harmony become accessible to rapid, universal, low-level, robust human inference mechanisms using image schemata such as containment, contact, centre-periphery, and source-path-goal. This process is more rapid, and imposes far less cognitive load, than slow, abstract symbolic reasoning. 2 Using the above principles, several versions of Harmony Space have been designed to exploit specific interaction styles for different purposes. We note some key variants, such as the desktop version (Holland 1994), the camera tracked version ), while focusing principally on the most recent version, Song Walker (Holland et al. 2011) , which employs whole body interaction. Preliminary results from a study of the Song Walker system are outlined, in which both beginners and expert musicians undertook a range of musical tasks involving the performance, composition and analysis of music. Finally, we offer a discussion of the limitations of the current system, and outline directions for future work.