Rhythmic Processes in Electronic Music

Electronic technology has liberated musical time and changed musical aesthetics. In the past, musical time was considered as a linear medium that was subdivided according to ratios and intervals of a more-or-less steady meter. However, the possibilities of envelope control and the creation of liquid or cloud-like sound morphologies suggests a view of rhythm not as a fixed set of intervals on a time grid, but rather as a continuously flowing, undulating, and malleable temporal substrate upon which events can be scattered, sprinkled, sprayed, or stirred at will. In this view, composition is not a matter of filling or dividing time, but rather of generating time. The core of this paper introduces aspects of rhythmic discourse that appear in my electronic music. These include: the design of phrases and figures, exploring a particle-based rhythmic discourse, deploying polyrhythmic processes, the shaping of streams and clouds, using fields of attraction and repulsion, creating pulsation and pitched tones by particle replication, using reverberant space as a cadence, contrasting ostinato and intermittency, using echoes as rhythmic elements, and composing with tape echo feedback. The lecture is accompanied by sound examples. The text is derived from a chapter on rhythm in my forthcoming book Composing Electronic Music: A New Aesthetic [1]. 1. RHYTHM IN ELECTRONIC MUSIC Music is a dance of waves: vibrating the air, the ear drum, the bones of the inner ear, and the auditory nerve, with the ultimate goal of stimulating electrical storms in the brain. In much electronic music, including my own, rhythm often emerges as the dominant element in a flux of ever-changing parameter interactions. Indeed, rhythm is the sum total of all parameter interactions. Today, rhythm can no longer be viewed merely as a pattern of notes on a page of score. We acknowledge the existence of a continuum from the pace of mesostructural boundaries (seconds and minutes), to infrasonic fluctuations (< 20 Hz) to events at all audio frequencies up to pulses at the sampling rate. Microsonic processes introduce the possibility of evaporation, coalescence, and mutation of sound materials, analogous to the ever-changing pattern of clouds in the sky. As a result, the precise rhythmic pattern of certain sound phenomena is far from clear. As these microstructural processes unfold, they result in the phenomena of perceived pitch, duration, amplitude, space, and timbre, all of which function as articulators of rhythm. Thus rhythm occurs as an emergent quality of triggers, phasors, envelopes, and modulators on a micro time scale. As Messiaen [2] pointed out, the perception of duration can be modulated by musical processes. We also know that human listeners construct rhythmic groups around events that are linked by Gestalt perception. In the late 20th century, rhythmic notation evolved over time into hyper-complexity, testing the limits of readability and playability. At the same time, the technology of electronic music made the design of complex rhythms ever more accessible. Indeed, technology has changed the paradigm of rhythmic theory and organization. The liberation of time from meter was enabled by the technologies of recording (with variable speed and backwards playback), editing, granulation, and programming. These capabilities have transformed the rhythmic playing field. Studio technology enables the exploration of polyrhythmic grids and fields. The new generation of sequencers and programmable clock sources lead into uncharted rhythmic territories. Ironically, the ability to stipulate rhythm precisely proved to be a barrier to naturally flowing rhythm in the early days of computer music, when the start time and duration of each event had to be typed in a long note list. The computer was an ideal vehicle for formally-oriented composers who wanted to distance themselves from habitual phrasing, but this same distance had to be overcome by composers and performers seeking more immediacy of expression. Thus an aesthetic tension remains between machinegenerated timings and the subtle body rhythms we naturally associate with virtuosic performance. The challenge in generative rhythm is to tame the urge to produce temporal minutiae that is fascinating only to the person who wrote the program that generated it. Listeners organize rhythmic perceptions according to Gestalt expectations and tend to simplify or group events together into a limited range of rhythmic patterns. We are exquisitely sensitive to and compelled by pulsation. However, pulse is not only the ubiquitous beat of popular music, but any form of periodicity, however fleeting and temporary, like the repetition of slapback echo or the flutter of low-frequency amplitude modulation. In the rest of this paper, I introduce aspects of rhythmic discourse that appear in my electronic music. The lecture is accompanied by sound examples. Copyright: © 2014 Curtis Roads. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. A. Georgaki and G. Kouroupetroglou (Eds.), Proceedings ICMC|SMC|2014, 14-20 September 2014, Athens, Greece