GRM Tools, created at the Groupe de Recherches Musicales (GRM) of Pierre Schaeffer, is a package of software and utilities for sound synthesis and processing. It was developed over a decade and was implemented even in VST and RATS environment.
The Nineties – For computer music, the nineties are configured as a time of great changes due to technological development which leads to the spread of increasingly higher performance computers. The research and production of GRM deeply affected by the changing situation. The years immediately preceding had been invested in research and the use of Syter, a system for real-time which was operational until 1995. This project was initiated by Jean-François Allouis. Later he moved at Ircam in Paris and the work was carried out by Hugues Vinet, which since 1988 was also responsible for management of the center founded by Pierre Schaeffer.
New orientation – At the same time to work on Syter, Vinet began experimenting with the use of the Macintosh computer in combination with the Digidesign devices and Sound Designer software and sound cards. His goal was to develop a system for control the Motorola DSP 56001 processor: from this was born the DSP Station. The new technological situation of the nineties led to the Syter obsolescence. The research had already begun to move towards the modern computer, compact and with outstanding performance. From this new direction came several new features: Midiformer (also called MacsOutiL), the Acousmographe and the GRM Tools. The latter is configured as a direct result of the work done by Vinet to the DSP Station.
First version – Although the GRM Tools was developed for over a decade, the first version, created in collaboration with Digidesign, was completed in 1992, implementing the software with Sound Designer sound cards. Initially aroused no particular interest, especially because compared to Syter was configured as a regression, since the smaller features with which it was equipped. On the positive side, however, there was the possibility of widening the spread of the GRM computer products, thereby increasing the community. Although this was an important aspect, the composers were interested in each other and for this many preferred to continue using the Syter.
Emmanuel Favreau – In 1994, Favreau was named chief engineer for the development of GRM Tools. The Favreau brought a series of changes that stimulated the interest of composers toward the GRM Tools. So, the GRM Tools, was adapted to Steinberg’s VST and Digidesign’s RATS. It was easier to use graphical interface and developed new algorithms, eight of which were adaptations of functions already adopted with the Studio 123 package and with Syter. Later they were released four new algorithms called GRM Tools ST that allowed sound processing. It was brought forward an approach based on a global manipulation of the material rather than on individual parameters, thus creating a continuity with the positions expressed by Pierre Schaeffer.
Interpolator – Among the other innovations introduced in the nineties, designed to increase the potential of the GRM Tools, we also remember one called Interpolator. The first version was developed by Martin Spain at University of Hertfordshire. It was a graphical interface, compatible with the VST format, which allowed the two-dimensional control in complex applications of GRM Tools. Part of this work is also inspired some solutions already adopted by Syter. In 2001, however, still Favreau, implemented in the GRM Tools (for VST and RATS environment) the technique of analysis/resynthesis of the Phase Vocoder.
For this topic I’ve read:
 Daniel Teruggi, Technology and musique concrète: the technical developments of the Groupe de Recherches Musicales and their implication in musical composition, Organised Sound, Vol. 12 , 2007.
 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 .
 Martin Spain, Richard Polfreman, Interpolator: A Two-dimensional Graphical Interpolation System for the Simultaneous Control of Digital Signal Processing Parameters, Organised Sound, Vol. 6 , 2002.
 Emmanuel Favreau, Phase Vocoder Applications in GRM Tools Environment, Proceedings of the XI Conference on Digital Audio Effects, Limerick, 2001