From interface design to the software instrument - mapping as an approach to fx-instrument building

To build electronic musical instruments, a mapping between the real-time audio processing software and the physical controllers is required. Different strategies of mapping were developed and discussed within the NIME community to improve musical expression in live performances. This paper discusses an interface focussed instrument design approach, which starts from the physical controller and its functionality. From this definition, the required, underlying software instrument is derived. A proof of concept is implemented as a framework for effect instruments. This framework comprises a library of real-time effects for Csound, a proposition for a JSON-based mapping format, and a mapping-to-instrument converter that outputs Csound instrument files. Advantages, limitations and possible future extensions are discussed.