“One of my long-term interests has been the invention of ‘machines’ and systems’ that could produce musical and visual experiences. Most often these ‘machines’ were more conceptual than physical; the point of them was to make music with materials and processes I specified, but in combinations and interactions that I did not.
My first released piece of this kind was Discreet Music (1975). ‘n which two simple melodic cycles of different durations separately repeat and are allowed to overlay each other arbitrarily. (Thus, for instance, if one cycle is 29 seconds long and the other 33 seconds long, they will come back into sync every 957 (i.e. 29 x 33) seconds. Subsequently I released Music for Airports, On Land, Thursday Afternoon, Neroli and other works, all of which use variations on this and similar ‘automatic’ systems.
In my audio-visual installations I found another way of making ever- changing music. I distributed the pre-recorded musical elements over several (usually four to eight) audio cassettes of different lengths. These were all played back simultaneously, each cassette feeding its own ampli fier and pair of speakers. It was thus possible to make music that was different at any point in space and time – or effectively so, because in fact the cassettes would have come into sync again after a few years, if any of the shows had lasted that long (e.g. five cassettes of lengths 23, 25.5, 30.2,19.7 and 21.3 minutes would fall into sync about every 14 years).
I enjoyed these shows – especially the knowledge that the music I was hearing at any given moment was unique, and would probably never be heard in exactly that way again.
My records, however, were always recordings of the output of one or another of these combinatorial systems: though it could produce original music forever, what went on the record was a 30-minute section of its out put, which would then of course be identical each time you played it. However, what I always wanted to do was to sell the system itself, so that a listener would know that the music was always unique. Since this would have involved persuading my listeners to buy four or five CD-players
instead of just one, and then buy the set of four or five CDs to play on them, I didn’t spend too much time on the project.
But with computer technology I began to think that there might be a way of doing it. I was inspired initially by certain screensavers – those little graphic devices that use very little computer memory but keep generating new images on the screen. I wrote several proposals based on the idea of using the computer to make music in a similar manner – not as a way of replaying huge chunks of preformed material (which was what was being done, to devastatingly miserable effect, with CD-Roms at the time) but instead as a place where compositional ‘seeds’ provided by the composer would be grown. I thought this made composing into a kind of genetic activity – in the sense that the compositional ‘seeds’ were actually interact ing sets of rules and parameters rather than precise musical descriptions.
I imagined the piece evolving out of the interaction of these probabilistic rule-sets – and therefore evolving differently in each ‘performance’.
Since I know nothing about writing code for computers, this would probably have remained a pipedream were it not for a company called Sseyo who had been thinking on exactly the same lines.
In early 1995 I received from them a CD of music that had been made by their software program called Koan. A couple of the pieces were clearly in ‘my’ style (they readily acknowledged that my ‘ambient’ work had been part of their inspiration for the Koan system), but what surprised me was that I would have been proud of them. I contacted Tim Cole at Sseyo, and he arranged for me to get a copy of the Koan ‘authoring tool’ – the pro gram by which one writes the rules for these pieces – and, after a few days of typical interface frustration, I took to it like a duck to water.
Koan works by addressing the soundcard in the computer. A soundcard is a little synthesizer sold as an optional add-on to the computer. The computer sends instructions to that soundcard and tells it what noises to produce and in what patterns. Koan is a very sophisticated way of doing this, enabling a composer to control about 150 parameters that specify things like sound-timbre and envelope, scale, harmony, rhythm, tempo, vibrato, pitch range, etc. Most of Koan’s instructions are probabilistic – so that rather than saying ‘Do precisely this’ (which is what a musical sequencer does) they say ‘Choose what to do from within this range of possibilities.’ The Koan program allows that range to be more or less specific-you could, if you so chose, write absolutely precise pieces of music with it, though this would probably be its least interesting use.
Some of the works I’ve made with Koan sound to me as good as any thing I’ve done. That’s important: they work as music and are not – as so much computer-based art has been – just a ‘neat idea’. They also symbol ize to me the beginning of a new era in music. Until 100 years ago every musical event was unique: music was ephemeral and unrepeatable, and even classical scoring couldn’t guarantee precise duplication. Then came the gramophone record, which captured particular performances and made it possible to hear them identically over and over again. But Koan and other recent experiments like it are the beginning of something new.
From now on there are three alternatives: live music, recorded music and generative music. Generative music enjoys some of the benefits of both its ancestors. Like live music, it is always different. Like recorded music, it is free of time-and-place limitations – you can hear it when you want and where you want. And it confers one of the other great advantages of the recorded form: it can be composed empirically. By this I mean that you can hear it as you work it out – it doesn’t suffer from the long feedback loop characteristic of scored-and-performed music.
Edgar Wind, in his 1963 Reith Lectures, said: ‘ It might be argued that, in the last analysis, listening to a gramophone or a tape recorder, or to any of the more advanced machines of electro-acoustical engineering, is like lis tening to a superior kind of musical dock.’ I too think it’s possible that our grandchildren will look at us in wonder and say, ‘You mean you used to lis ten to exactly the same thing over and over again?’
The idea of generative music is not original to me (though I think the name is). There have been many experiments towards it over the years, and indeed a lot of my interest was directly inspired by Steve Reich’s six ties tape pieces such as Come Out and It’s Gonna Rain. I think, however, that this new linkage with an increasingly commonplace technology will make this an area that many composers and listeners will want to explore.”
— Brian Eno, Generative Music, from A Year With Swollen Appendices, 1995