Realtime Representation and Gestural Control of Musical Polytempi

Over the last century, composers have made increasingly ambitious experiments with musical time, but have been impeded in expressing more temporally-complex musical processes by the limitations of both music notations and human performers. In this paper, we describe a computer-based notation and gestural control system for independently manipulating the tempi of musical parts within a piece, at performance time. We describe how the problem was approached, drawing upon feedback and suggestions from consultations across multiple disciplines, seeking analogous problems in other fields. Throughout, our approach is guided and, ultimately, assessed by an established professional composer, who was able to interact with a working prototype of the system.