Signal Processing as Practice: Trial-and-Error Revision of the Sensorimotor Dynamics of a Hybrid Violin

This paper describes the evolution of a "hybrid violin" developed and played by the author and reflects on the process of developing its sensorimotor dynamics as a salient affordance of real-time digital signal processing. The hybrid violin consists of a technical ensemble of hardware and software elements, including an acoustic violin, microphone, custom sensor glove (alto.glove), and customized ergonomic shoulder rest embedded with voice coils for haptic feedback coupled to digital audio output. Through trial-and-error revision by the designer, sensory feedforward and feedback paths are effectively symmetrized, thereby engaging the claim of the "enactive" approach to cognition as a creative practice: perception drives action and action drives perception. The hybrid violin catalyzes improvised performance insofar as it is responsive to all gesture and embeds no assumptions about expressive intention. The system allows for experimentation with violin technique by continuously and intensively tracking gestural and auditory inputs.