The DSP Station is a system developed at the Groupe de Recherches Musicales (GRM) of Pierre Schaeffer for the Motorola 56001 processor control. It was designed to work in deferred time and real time, and was conceived as a tool useful for the composition, teaching and research in the perspective of computer music.
Brief history – Since the early nineties, thanks to technological development that has made available more powerful computers but with reduced size and cost compared to the old mainframes, Hugues Vinet began working on the development of suitable applications to the new context. His work, initially, was oriented towards the implementation of systems for control of the Motorola 56001 digital signal processor.[1] From this work, the project took the form of DSP Station.
Technical aspects – The DSP Station was thus built for Macintosh computers, and to interact with HyperCard software, used to build GUI management. These elements are added to the Sound Tools hardware, manufactured by Digidesign. A very similar software had already been built by Adrian Freed, the HyperDSP, but at the GRM was not considered to meet the needs of those engaged in concrete music.[2] The DSP Station was designed to work both in real time and deferred time. Its features made it a useful tool not only for the composition, but also suitable for teaching and research.
The main features – The Groupe de Recherches Musicales project was based on three fundamental aspects: the use of a processor Motorola DSP56001 (for this processor is programmed macros for handling sound input and output, the sound signal processing and hardware communication), then the GUI and, finally, a set of algorithms, both generic type and specific to certain operations. Both of these types were supported by customized graphical user interfaces control.
Other features – Among other features available to the user, it was possible to get mono and stereo output. Furthermore, the user could have marker customizable in position to pull loop from the overall sound material. The processor could be controlled and managed by alphanumeric code written on dedicated file.[2]
The virtual interface – For real-time control of parameters, however, the DSP Station was equipped with two-dimensional faders “on screen”, and a display for viewing. Management software allows you to specify which parameters to be checked using the faders. HyperCard software, however, was used to resolve issues related to management of the graphic environment.
Processing algorithms – As for algorithms, there are three main groups: the first of a general nature (in which we find different types of filters, low/high/band pass, and algorithms for time stretching). The second group, however, was more oriented to sounds processing and synthesis (was integrated additive synthesis, ring modulation, Doppler effect, resonant filters and algorithms for the definition of micro-loops). The third group, however, was dedicated to the restoration of old recordings (some of which made it possible to mitigate noise.).[2] The design of the DSP Station inaugurated the research activities that are oriented, as in this case, to the development of software for small computers. In this sense, the DSP Station provided an important contribution to the next work for the package called GRM Tools.
For this topic I’ve read:
[1] Yann Geslin, Digital Sound and Music Transformation Environments: A Twenty-year Experiment at the “Groupe de Recherches Musicales”, Journal of New Music Research, Vol. 31 N. 2.
[2] Hugues Vinet, Olivier Koechlin, Didier Brisson, DSP Station, a HyperCard Environment for DSP Sound Processing Algorithms, Proceedings of International Computer Music Conference, McGill University, 1991.