Permutation synthesis

This paper introduces an experimental digital sound syn- thesis technique called Permutation synthesis, which fo- cuses around creating new waveforms by moving groups of samples (chunks) of existing waves. Similarly to granular synthesis, permutation synthesis is a time-based technique, i.e. it operates directly on the discrete waveform: by means of varying the length of the chunks, several perceptual ef- fects can be obtained. The most important parameter in permutation synthesis is the permutation frequency, which is inversely proportional to the chunk length; the resolu- tion of this parameter is directly related to the sampling frequency (given the fact that a chunk is always an integer number of samples), thus a time-quantisation error is de- fined. An algorithm for real-time permutation implemented as a SuperCollider plug-in is described, consisting of 3 UGens performing permutation synthesis in slightly different ways. The resulting signals are then analysed and their time and spectral effects are justified by defining formulas that ana- lytically quantify the results.