What is granular synthesis, and what can I do with it?
Granular synthesis is, in a nutshell, the process of creating new sounds using tiny fragments of existing sounds. These fragments of sound are normally referred to as 'grains', hence the term 'granular' synthesis. The idea that sound itself consists of particles goes back to 1947, when the physicist Denis Gabor presented his article "Acoustic Quanta and the Theory of Hearing" in the journal Nature. Some early proponents of granular techniques in music are the composer Iannis Xenakis (for example, listen to the great orchestral work Pithoprakta from 1955), Curtis Roads (probably the first guy to perform granular synthesis techniques with computers) and Barry Truax (listen to his seminal work Riverrun from 1986). I could go on forever about the science and theory behind granular synthesis, but I don't think this is the appropriate place to do so, since only a basic understanding of the technique is necessary for using RTGS. Anyone really interested in granular synthesis theory might want to check out Curtis Roads' "Computer music tutorial" (MIT press, Mass 1994).
Granular synthesis can be used to generate brand new sounds or to manipulate and distort existing sounds. It is very useful in generating dense sonic textures, which can evolve quickly or over long periods, to create alien soundscapes. It is also useful for creating short sound effects or sonic motives, which could be used in musical or theatrical situations. One of the most interesting applications of granular synthesis is the manipulation of existing sound through temporal distortion (time stretching, compression, reversal, and fragmentation). Taking a short sample of a sonically rich sound and stretching it to a hundred times its original length can yield some remarkably interesting results! I have been able to generate some wild, interesting and fresh sounds using granular synthesis. What I like most about it is that it is possible to generate sounds which have a certain "natural" quality to them, unlike sounds generated using FM or other oscillator-based synthesis techniques. I hope that in your exploration of granular synthesis you will also find sounds that stimulate your senses and creativity!