Feedback, the circular process by which the effects of a system interact with their own causes, was undoubtedly one of the most important cultural determinants of the twentieth century. Alan Turing’s calculators, John Von Neumann’s automata and Norbert Wiener’s cybernetics all contributed to the emergence of a new kind of digital machine with anthropomorphic pretensions, and to the concretization of age-old mechano-morphic thinking, which equates all human production, especially intellectual production, with the result of a calculation.
In sound engineering, the feedback loop of a minimal electroacoustic installation can produce a Larsen effect, well known to sound engineers and musicians. The result is a sinusoid of maximum amplitude, modulated by the characteristics of its environment. Resonance no longer takes place only within the body of an instrument, in order to stabilize a pitch; it now extends to the space of an entire audience. Alvin Lucier (1931 – 2021) created a reflexive, emblematic work: I am sitting in a room (1969), in which the tape recorder iteratively records its own broadcast of a text, read by the composer, describing the device itself.
The greater the computing power, the more feedback thinking is likely to change the traditional conception of a musical work. Instead of an order of precedence running from the composer to the score, then from the performer to the listener, the incursion into the musical field of a calculation “as fast” as hearing can be enables music in situ, which integrates the dynamic response of its place of emission into the phenomenon it conjures up. Where a feedforward work must anticipate the normality of the sound space in order to unfold, feedback makes possible this other relationship, where the real conditions of sound propagation modify the logic of the writing in real time, or at least its expression by the machine.
- Lecture for Cursus 2022-2023 students, Salle Messaien, IRCAM, Paris