Lexikon-Sonate. An Interactive Realtime Composition for Computer-Controlled Piano

Karlheinz Essl

SAMT - Studio for Advanced Music Technology
Hagenberg/Linz - Austria - Europe


Lexikon-Sonate is a work in progress which was started in 1992. Instead of being a composition in which the structure is fixed by notation, it manifests itself as a computer program that composes the piece - or, more precisely: an excerpt of a virtually endless piano piece - in real time. Lexikon- Sonate lacks two characteristics of a traditional piano piece: 1) there is no pre-composed text to be interpreted, and 2) there is no need for an interpreter. Instead, the instructions for playing the piano - the indication "which key should be pressed how quickly and held down for how long" - are directly generated by a computer program and transmitted immediately to a player piano which executes thern. In this paper I will describe from where I started and how I arrived at the concept of an infinite interactive realtime composition.