Composition Directives

Nine pitch classes of the Bohlen-Pierce scale are spread over the range of five octaves going from roughly F2 in the traditional well tempered scale up to D7. Each pitch class is assigned five or seven rhythmic pattern permutations. Each permutation constitutes a sound-file or a track. CD tracks are then randomly ordered to fill a 74 minute compact disc. In the software case (PD) these five or seven sound-files are chosen by the visitor or player either by choice or by probability distributions (weights). Once the user has selected a sound-file, its performance can be aborted with a fade choice or just cut. If the player's performance is satisfactory and the listener content, sound-files can be manipulated by changing their amplitude, speed, speaker assignment, panning, or proximity. Performance can be stopped at any time. Whether the first player is performing or not is not an issue for adding a second player with similar or different options as the first one. Similarly with a third one and, so on. Rhythmic structures are manipulated by rhythmic super-position and phase. Intervals are created by connecting sounds in one track with the others. Total duration in this experience is expected anywhere from 20 seconds to several minutes.

Figure 2: Algorithm