Sound synthesis with totalistic rule cellular automata

Abstract

Cellular Automata (CA) and their emergent structures have been used to synthesize sounds because of their unique and unpredictable patterns which cannot be possible with traditional synthesis methods. This study presents a novel sound synthesis procedure using one-dimensional totalistic rule CA. The procedure converts the histogram of CA states per timestep into a spectrogram, where different states correspond to different frequencies, similar to the Histogram Mapping Synthesis method by Serquera and Miranda [Comput. Music J. 38, 38 (2014)]. Various sound clips were generated for four different CA rules − Ascending, Descending, Ascending Descending, and Consecutive Ascending − referring to the pattern in the digits of the totalistic rule we defined. All of the synthesized sounds have a sawtooth electronic sound quality that is similar to the synths used in the industrial electronic music. The different rules produced a diversity of sound patterns: sound that consistently oscillates between two pitches, sound with oscillating pitch that stabilizes to a single pitch, resembling a flatlining ECG heart monitor, sound that consistently oscillates between three pitches, and sound of apparently random pitches. These results point to a promising approach for sound synthesis and design using a rich suite of Cellular Automata.