Expanding the machine: Notating generative synthesis with a state-based representation and a navigable timbre space

Abstract Notating electroacoustic music can be challenging due to the uniqueness of the instruments employed. Electronic instruments can include generative components that can manipulate sound at different time levels, in which parameter variations can correlate non-linearly to changes in the instrument’s timbre. The way compositions for electronic instruments are notated depends on their interfaces and the parameter controls available to performers, which determine the state of their sound-generating system. In this article, we propose a notation system for generative synthesis based on a projection from its parameter space to a timbre space, allowing to organise synthesiser states based on their timbral characteristics. To investigate this approach, we introduce the Meta-Benjolin, a state-based notation system for chaotic sound synthesis employing a three-dimensional, navigable timbre space and a composition timeline. The Meta-Benjolin was developed as a control structure for the Benjolin, a chaotic synthesiser. Framing chaotic synthesis as a specific instance of generative synthesis, we discuss the advantages and drawbacks of the state- and timbre-based representation we designed based on the thematic analysis of an interview study with 19 musicians, who composed a piece using the Meta-Benjolin notational interface.