WHEEL ME OUT - John Eacott

Musician John Eacott has played in jazz, pop and experimental groups and composed for TV and film. Over the past decade he’s turned his attention to algorithmic composition and his latest piece, Flood Tide, a sonification of the Thames, will be performed at this year’s Thames Festival.

Interview by Ananda Pellerin

Describe algorithmic composition for us. It’s a branch of computer music that began in the 1950s when computing began to boom. Then from around 1990 home computers have been powerful enough for people to do their own real-time algorithmic pieces, often called ‘generative pieces’, by writing a piece of software to which they delegate the act of composing.

So the craft then is in writing the computer programme, rather than in creating the music? It fuses both in a very satisfying way. It depends on some computer programming expertise but in order to programme you've got to have the musical ideas that you want to put into it. In order to write a generative piece you're asking yourself “what do I do when I make music? How can I break that down into suitable, code-able rules that this computer can use?”

Your more recent piece is based on computer-generated notation that describes the changing tidal flow of the Thames, read by sensors and finally performed by live musicians. How did you get this idea? I've been exploring algorithmic processes for a while now and one of the common ways of creating generative pieces is to use a random number generator. I love the use of chance in music but I wanted to find sources to drive my algorithms that weren't random.

Flood Tide and Hour Angle, another piece of mine, are siblings in a way, with Hour Angle sonifying the movement of the sun and Flood Tide sonifying the movement of tidal water. I love sailing, traditional navigation methods and meteorology, which are all closely related to these pieces.

Of course I'm not the first to do this, there's a whole movement of people sonifying things — weather data, the stock market, all kinds — taking non-musical information and turning it into sound. I'm just one of those.

What does Flood Tide sound like? I made a conscious decision to make it overtly tonal and quite harmonic. Tide is very steady and predictable so while interpreting tide we wouldn't expect anything too turbulent, however it does increase in pace and those changes can be quite dramatic.

And you never get the same piece of music twice? Yeah. There are many kinds of generative music but it’s almost a given that it tends to be involved with uniqueness. I find the whole area of generative arts is a reaction to the linear media arts of the 20th century, things like recordings, film, video - which are massively important but I feel we've got to an age now with digital processes where we don't need fixed artefacts any more, it's more interesting to create artefacts that have the ability to respond or think for themselves; to give them a kind of life.

You’ve chosen to have live performers interpreting the computer-generated notation. Why did you decide this? I’ve done quite a few pieces that created electronic sound and I may well come back to that but fundamentally, as a jazz musician and a trumpeter, I'm most excited by live performance. Hour Angle and Flood Tide are both entirely acoustic - so far we haven't performed with any amplification at all. For Flood Tide I’m keen to have the acoustic sound of the instruments played alongside the river so you actually hear the sound of the water and it becomes a bit of an environmental oneness.

You mentioned you got some of your equipment from the National Oceanography Centre in Southampton. They have an amazing array of gizmos - from simple sensors like the one I’m using to buoys that get dropped in the water and left for years and are tracked all over the world. I’ve got an acoustic path transducer which uses the Doppler effect; it emits a sound signal from a terminal which is picked up by another terminal. Then as the medium it's moving through — the water — changes in speed, it effects the time it takes to get from one terminal to another. It’s a pretty simple principle but it's allowed me to get accurate, sensitive readings of the tide.

What’s happening with Flood Tide at the Thames Festival this year? I'm doing a series of performances over fourteen days in a barge house near the OXO tower on Millbank, where we’ll play a ninety minute segment at the same time each day, so you'll be able to hear the tide in a slightly different phase because it occurs roughly an hour later each day.

Then on the final day we’re going to do a performance of the whole incoming tide, taking around six hours, outside by the Thames. It's deliberately a kind of ambient work where people can stroll by and listen for a while, move on, maybe come back later to see how it's changed. It's a big experiment for me.

How have performers responded to performing Flood Tide? The musicians are sight-reading all the time. Even though we can practice they don't know precisely what will come out and what I’ve discovered is that musicians quite enjoy it, they like the challenge of remaining focussed.

At the Thames Festival I’ll probably use three musicians but for the main, six-hour performance I'm hoping to collaborate with the Centre For Young Musicians in Waterloo and put together a 32-musician ensemble which will allow for a much bigger dynamic range.

What will you do while the musicians are performing? Once I've made sure the process is all working I’ll just sit back and see what happens. WMO

John and The Thames Festival. Here’s the score

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