Cybernetic Systems

Shannon wasn’t the only one looking at the way signals were transmitted. The same year he published his breakthrough paper, another mathematician published a book that would leave a lasting impression on a number of different fields, electronic music among them. The man was Norbert Wiener and his book was Cybernetics: or control and communication in animal and machine. Wiener defined cybernetics as "the scientific study of control and communication in the animal and the machine".

Wiener was a child prodigy. Born to Polish and German Jewish immigrants, on his fathers side Nobert was related to Maimonides, the famous rabbi, philosopher and physician from Al Andalus. The predisposition to intellectual greatness was hardwired into his system. Norbert’s father Leo was a teacher of Germanic and Slavic languages and avid reader and book hound who put together an impressive personally library which his son devoured. His father also had a gift for math and gave his son additional instructions in the subject.
At age 11 Norbert graduated Ayer Highschool in Massachussettes and then began attending Tufts College where he received a BA in mathematics at the age of 14. From there he went on to study zoology at Harvard before transferring to Cornell to pursue philosophy, where he graduated at the ripe old age of 17 in 1911, when his classmates from Ayer were probably just entering college if they went at all. Then he went back to Harvard where he wrote a dissertation on mathematical logic, comparing the works of Ernst Schröder with Bertrand Russel and Albert North Whitehead. His work showed that ordered pairs could be defined according to elementary set theory. His Ph.D. was awarded before he turned twenty. Later that same year he went to Cambridge and studied under Russel, as well as at the University of Göttingen where to learn from Edmund Husserl.

After a brief period teaching philosophy at Harvard, Wiener eventually found a position at MIT that would become permanent.  In 1926, Wiener returned to Cambridge and Göttingen as a Guggenheim scholar, on a trip that would have important implications for his future work. He spent his time there investigating Brownian motion, the Fourier integral, Dirichlet's problem, harmonic analysis, and the Tauberian theorems.

​Harmonic analysis and Browninan motion in particular would go on to have a key role in the development of cybernetics.

Harmonic analysis is a branch off the great tree of math that is concerned with analyzing and describing periodic and recurrent phenomena in nature, such as the many forms of waves: musical waves, tidal waves, radio waves, alternating current, the motion and vibration of machines. And it branched off the research of French mathematician Joseph Fourier (1768-1830). Fourier was interested in the conduction of heat and other thermal effects, a trail later followed by Nyquist in his own investigations of thermal noise. 

According to the Encyclopedia Brittanica the motions of waves  “can be measured at a number of successive values of the independent variable, usually the time, and these data or a curve plotted from them will represent a function of that independent variable. Generally, the mathematical expression for the function will be unknown. However, with the periodic functions found in nature, the function can be expressed as the sum of a number of sine and cosine terms.” The sum of these is known as a Fourier series. The determination of the coefficients of these terms is became known as harmonic analysis.

Brownian motion or movement relates to a variety of physical phenomena where some quantity of substance undergoes small and constant but random fluctuations. When those particles that are subject to Brownian motion are moving inside a given medium, and there is no preferred direction for these random oscillations to go, the particles will over time, spread out evenly in the substance.

Both Browninan motion and harmonic analysis can be considered stochastic processes. A stochastic process is, at its core, a process that involves the operation of chance. It is a process where values change in a random way over time. Markov chains are another important form of stochastic process that has been applied to music. Stochastic process can also be used to study noise, and Wiener was a student of this mathematical noise.

Amidst the conflicts of WWII Norbert was called upon to use his prodigious brain for solving technical problems associated with warfare. He attacked the problem of automatic aiming and firing of anti-aircraft guns. This required the development and further branching of even more specialized math. It also introduced statistical methods into the recondite area of control and communications engineering, which in turn led to his formulation of the cybernetics concept.

His concept of cybernetics was eerily close to Claude Shannon’s information theory. What they both had in common was knowledge of the influence of noise and the desire to communicate or find signals in, above, and around the noise. One of the ways Wiener figured out how to do this was through filtering. Enter the Wiener filter. It works by computing statistical estimates of unknown signals using a related signal as an input and filtering that to produce an estimated output. Say a signal has been obscured by the addition of noise. The Wiener filter removes the added noise from the signal to give an estimate of the original signal.

Cybernetics is also related to systems theory, and studied in particular the idea of feedback, or a closed signaling loop. Wiener originally referred to the way information or signals effect relationships in system as “circular causal”. Feedback occurs when some action within the system triggers a change in the environment. The environment in turn effects another change in the system when it feeds back the now transformed signal into the originating source.  Wiener, through his study of zoology was applicable to biological and social systems, as well as the mechanical ones his research had originally grown out of. Cognitive systems could also be understood in terms of these circular causal chains of action and reaction feeding back in on itself.

Cybernetic’s essential idea of feedback was also directly applicable to the new electronic musical systems defined by the advent of the microphone, amplifier, and speaker. When these devices are connected together in a circuit audio feedback is one possible result stemming from holding the mic close to the speaker. Everyone has experienced the unintentional noise when a PA is being tested. Musicians quickly adapted the idea of using intentional feedback, and distortion (noise on a signal) to give their recordings and live performances a new sound.

Cybernetics is not limited to mapping the flow of information, distorted or otherwise, in and out of systems. It also includes concepts of learning and adaption, social control, connectivity and communication, efficiency, efficacy, and emergence.
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The related fields of information theory, cybernetics and systems theory would have huge impacts on music and the arts, as the theories trickled down from places like Bell Labs, the Macy Conferences with their focus on communication across scientific disciplines, and the success of Wiener’s book outside of strictly scientific circles.

The word cybernetics sounds kind of cold and inhuman. It conjures up the chrome clad computerized villains made famous by Doctor Who, the cybermen who speak only in monotone and whose overriding program is to delete organic life. Yet the word cybernetics itself comes from the Greek kybernḗtēs, or "steersman, governor, pilot, or rudder.” Human systems require a guide, someone to steer them. Wiener had picked up the word from the French mathematician and physicist André-Marie Ampère who coined the word "cybernetique" in an 1834 essay on science and civil government. Governments and other systems of human invention require steersman and guides with a firm hand on the rudder to give direction and control the effects of feedback.
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The creation of systems is a human trait, and their guidance, via our input, doesn’t have to be cold. It can be done with intuition, insight, and artistic flair. Writing on systems in the world of art for the 1968 Cybernetic Serendipity art and music show at the ICA gallery in London, Jasia Reichardt wrote, "The very notion of having a system in relation to making paintings is often anathema to those who value the mysterious and the intuitive, the free and the expressionistic, in art. Systems, nevertheless, dispense neither with intuition nor mystery. Intuition is instrumental in the design of the system and mystery always remains in the final result."

The Discreet Music of Brian Eno
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Designing musical systems can result in extraordinary beauty. In the mid-1960s while attending Ipswich Art School Brian Eno had his first encounter with cybernetics. It would go on to have a lasting influence. Under the mentorship of Roy Ascott who had developed the controversial “Groundcourse” curriculum adopted by a number of other art colleges Eno absorbed Ascott’s philosophy of systems learning, making mind maps, and playing mental games.

Eno started thinking of the music studio and groups of musicians in terms of cybernetic systems. Making great musical compositions started with designing the parameters, limits, inputs and outputs that would give a composition its ultimate form. Creating these systems and letting them run was how many of his first, and the first, ambient music records were made. 

The liner notes for Eno’s 1975 album Discreet Music contain a block diagram of the system he created for the music. He had been given an album of 18th century harp music to listen to while laying in the bed in the hospital, where he was recovering from a car accident injury. A friend who had been visiting put the record on for him before she left but the volume was turned down too low. Outside it was raining and he listened to “these odd notes of the harp that were just loud enough to be heard above the rain.” The experience “presented what was for me a new way of hearing music—as part of the ambience of the environment just as the color of the light and the sound of the rain were parts of that ambience.”

Eno connected this experience to Erik Satie’s idea of “furniture music” that was intended to blend into the ambient atmosphere of the room, and not be something focused on directly. Furniture music could mix and combine with the sounds of forks, knives, tinkling glasses and conversation at a dinner.

After Eno’s listening experience in the hospital he set out to make his own ambient music, setting off a musical cascade and defining and kick-starting a genre that at the time of this writing is now forty-five years old.

In the liner notes to Discreet Music, Eno wrote these now famous lines, “Since I have always preferred making plans to executing them, I have gravitated towards situations and systems that, once set into operation, could create music with little or no intervention on my part. That is to say, I tend towards the roles of the planner and programmer, and then become an audience to the results.”

The liner notes also contain a block diagram of the system he set up. Eno had wanted to create a background drone for guitarist Robert Fripp to play along with. He was working with an EMS Synthi AKS with built-in memory and a tape delay system. He kept being interrupted in his musical work by knocks on the door and phone calls. He says, “I was answering the phone and adjusting all this stuff as it ran. I almost made that without listening to it. It was really automatic music.”

Discreet music started with two melodic phrases of differing lengths played back from the digital recall of the synth. That signal was then ran through a graphic equalizer to change its timbre. After the EQ the audio went into an echo unit and the output of that was recorded to a tape machine. That tape runs to the take-up reel of  a second tape machine, whose output is fed back into the first machine which records the overlapping signals and sounds. When Fripp came by the next day to have a listen Eno accidentally played the recording back at half-speed. Eno says of the result “it was probably one of the best things I’d ever done and I didn’t even realize I was doing it at the time.”

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Autonomous Dynamical Systems

Another example of musical systems in practice comes from the work of David Dunn. David is a composer, sound artist, bioacoustics researcher and an expert at making audio recordings of wildlife. A deep interest in acoustic ecology informs his work. Ecological thinking and systems thinking go hand in hand and this sensibility is present in many of David’s works.

His 2007 album Autonomous Dynamical Systems touches on ecology, fractals and chaos theory, graphic imagery to sound conversions, and feedback loops. The album consists of four compositions. Lorenz from 2005 is a collaboration with chaos scientist James Crutchfield. James has a long history of work in the areas of  nonlinear dynamics, solid-state physics, astrophysics, fluid mechanics, critical phenomena and phase transitions, chaos, and pattern formation, having published over 100 papers in his field of mathematics and physics.

The Lorenz attractor was first studied by meteorologist Edward Lorenz in 1963. He derived the math from a simplified model of convection in the earth's atmosphere and is most frequently expressed as a set of three coupled non-linear differential equations. In popular culture the idea of the “butterfly effect” comes from the physical implications of the Lorenz attractor. In any deterministic nonlinear system one small change, even the small disturbances in air made by the flight of a butterfly, can result in huge differences to the system at a later time. This shows that systems can be deterministic and unpredictable at the same time. When the Lorenz attractor is plotted out graphically it has two large interconnected oval shapes resembling a butterfly or a pair of wings.

For the piece Lorenz, David Dunn used a piece of software written by Crutchfield called MODE (Multiple Ordinary Differential Equations) plugged into the interface program OSC (Open Sound Control), a networking protocol that allows synthesizers, computers, and other multimedia devices. OSC is then in turn fed into sound synthesis program. The sound synthesis program is then fed back into OSC and again into MODE. The entire piece is a feedback loop originating from chaos controlled sound. As such its structure embodies the very principles it seeks to express as music. Another piece on the album, Nine Strange Attractors from 2006 steps up the game even further in its creative use of mathematics to explore feedback loops.
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Another piece uses feedback loops in a different way. Autonomous Systems: Red Rocks from 2003 used environmental field recordings fed into computer systems. Saved in the memory a chaos generator program chooses from among the sounds in a non-linear fashion and plays them back, sometimes electronically transformed, other times not. The composition is done, not by performing live, but by setting up and programming the system, then stepping away, sitting back, and listening to the results.   
John Cage said, “My compositions arise by asking questions.”  The music of systems proceeds from this same curious spirit. When designing new electronic works the composer must begin by asking questions of herself. Then systems can be designed to ask that question in different ways and to find out different answers. 

Wobbly and his Smart Phone System

Wobbly, aka Jon Leidecker, a solo artist, member of Negativland, and now host of radio show Over the Edge after the death of Don Joyce has also made a very interesting album by working with systems.

Between 2015 and 2018 Wobbly worked on an album called Monitress, released in 2019. He created an innovative system leveraging musical pitch tracking apps and synthesizers on a group of mobile phones and other mobile devices. Each of the devices was sent an audio signal. This was picked up by the pitch tracking app and coverted to MIDI data used to drive the synth. The resulting sound is then fed into an analog mixer. Once the signal is going into the mixer it can be routed and fed back into another mobile device also running a pitch tracking app and synth. The resulting effect is a cascade of sound between the devices.

​As Jon writes in the liner notes for the album, “ Feedback loops similar to acoustic or electrical feedback occur when you close the circle. The pitch-tracking apps are prone to errors, especially when presented with complex multiphonics or polyphonies;  they get quite a few notes fascinatingly wrong.  But more striking is the audible reality of their listening to each other.  Unison lines are an elemental sign of musical intelligence; we are entrained to emotional reactions when hearing multiple voices attempting the same melody.  These machines may not meet our current criterion for consciousness, but every audience I’ve played this piece in front of quickly realizes they're not listening to a solo…

The technology used to create these sounds existed before the mobiles, but this music would not have been made on earlier equipment -- it's a result of the relationship developed with a machine that is always present, and always listening. This was the project I dug into as we woke up to the true owners of these tools, a frame to make the relationship between ourselves and our machines audible while we think about the necessary steps to take next.”

The textures on this album are sublime, the kind of things that could only be heard through this a cascade of forces, each triggered by the preceding and affecting the whole in tandem. Wobbly did do post production editing of this work, but the initial results he captured once the process was set in motion is where the real magic lies. This is the kind of music that can’t be predicted. It couldn’t be written by a composer note for note. Rather the job of the composer is to design systems capable of eliciting beauty.
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The three examples of systems music explored here are only a few of many. Musical systems is a large category within the new common practice generally. Other ways of thinking about it is in terms of modular set ups, various configurations of test equipment, systems of feedback in the way guitar pedals are arranged, and more. I don’t know if Norbert Wiener ever thought of music as one of the places where cybernetics would take flight. To hear the music made with its principles is an artistic way of exploring the rich ecology of sound.  

Read the rest of the Radiophonic Laboratory  series. 

References: 

The Information: a history, a theory, a flood by James Gleick, Pantheon, 2011

A Mind at Play: How Claude Shannon Invented the Information Age by Jimmy Soni and Rob Goodman, Simon & Schuster, 2018

Encyclopedia Britannica: https://www.britannica.com/science/harmonic-analysis

Brian Eno, Discreet Music, Obscure Records, 1975

David Dunn,  Autonomous and Dynamical Systems, New World Records 2007

Wobbly, Monitress: https://hausumountain.bandcamp.com/album/monitress