Compositional Rules

New clm instruments based on the PhISEM model of the maraca were derived in order to achieve the timbres previously described in a customized to taste programs called mymaraca.ins and maracon.ins. Their interfaces work by manipulating coefficients of the gourd resonant filters and by changing rates of shake and shake energies. maracon.ins is a huge and resonant maraca with some seeds and a list of resonances depending on the gesture with or without a low-pass filter (the model without a low-pass filter gives a bell-like tone. Furthermore an instrument called jrnoise.ins which takes model parameters to the edge was developed to achieve a constant or slow motion sound of the maraca or the guiro. A score file called wadimusa.clm written in clm Lisp was created to dynamically change parameters on these instruments. The rendering of this composition results in known rhythmic patterns with ultra slow or fast tempos, polyrhythms, changes in the spectrum and musical gesture generation. Most gestures are time dependent and are produced by contrasting different sounds of familiar qualities as follows in the next sections. Some of these procedures are suggested by Garton in his virtual performance model [2, Garton, 1992].