Transduction, unheard music and Dreams of a Debauched Dodo
May 15, 2012
A while ago, in 2000, I gave a paper at a conference on Art and Science of Extraterrestrial Message Composition. The conference was co-sponsored by SETI and by Leonardo, and Doug Vakoch wrote up a nice article afterwards.
I was interested in the physiology of sound, how our shaping of sound represents our bodies.
My brief was that if we performed analysis on a large enough sample, we could identify some generic gestures, probably based on units of basic metabolism, and use that as material to construct an outbound message to ET.
The tool for this was the spectrogram, which I started to write about in an earlier blog on Fourier transform. The spectrogram takes 'sound' out of 'music', presents the material as an artifact outside of culture.
“A Waveform in one medium holds meaning in second. The Paris paper started to suggest the idea of sound as an architectural object. We could take all these sonic objects ("pieces of music"), create a morphology of generic structures, then transduce those to the electromagnetic spectrum.
(Elsewhere, I've commented on limitations of radio astronomy as the format for ET communication.)
The key to transduction is a shared measurement of Frequency. Everything that unfolds in time can be measured with a frequency. If something happens 10,000 times per second (10,000 Hertz) in air, it can happen 10,000 times in electromagnetism. Or in water. Or soil. Or if it happens once every 1017 seconds
To reiterate: when I say 'music', here I am not referring to cultural styles. I am referring to the conscious manipulation of pattern as represented by a waveform that can be applied to any medium.
This handwritten graph sketches out the idea. At the center is a linear axis, exponential values representing frequency from Zero to Infinity.
1 cycle per second, (1Hz) is the human heartbeat.
The chart breaks down into bands of activity, representing different sources of data, different medium. I've been talking about Electromagnetism and the Audible Spectrum, both shown here: but I also wanted to include biological, seismic, galactic time scales. As the chart is developed I expect to include other animal characteristics such as whale song and insect noise. I show diurnal activity (ocean tides), the solar calendar and then a jump up to the current age of the universe. I could also draw a block that represents the frequency of the martian orbit, the rotation of the Milky Way, the Age of Aquarius or the frequency of a human life.
The graph represents transduction as a jump between bands - for example from audible to electromagnetic, or seismic to sonic. This is more than just manipulating pitch to represent data. There is a 3 dimensional mathematical artifact that is moving between media.
If we take the frequencies of Visible light (let's say around 1015 ) and Transduce that to Audible, we are first changing the mechanism generating the energy so that now energy moves through. But we also need to consider Transposition. 1015 if played on an instrument ( a hell of an instrument) is far beyond the range of human hearing. Although sonoluminescence is an intriguing possibility. But for us to 'hear' the pattern created by light, the number needs to be divided down so that it is more like 103 .
The math is interesting, because the fundamental relationships between frequencies are ratios rather than exact measurements. The energy required to double the frequency is always the same. To move from 440Hz to 880Hz requires the same energy as moving from 44000hz to 88000Hz. Higher frequencies have a lower energy distribution.
Back to Paris for a moment. The output of Fast Fourier Transform (FFT) is a series of time-sequenced frequency arrays, which suggested to me that using some kind of algorithmic analysis (maybe humdrum?) I could look for shared sequences across a wide body of recorded samples. Those sequences could occur in any of the measurable vectors - beginning with pitch, but also looking for patterns in the overtones, shared sequences of amplitude changes.
(I've also thought that this could be a useful approach to whale song. The analysis of whale song I've seen has assumed that change in pitch generates a bit of information - but if we were to apply that method to the Hildegaard sample I presented in Paris, we'd miss all the meaning. I would propose an analysis of whale song that considers the periods of silence as a signifcator, or looks for patterns of changing amplitude at certain subsonic frequencies.)
The paper was really more a musing on the subject. I also played a recording of a composition. I was starting to think about composition in these generic terms. Along with a didgeridoo, I used electronics to create other drones, pulses, nothing you would call a beat - repeated surges and upwellings. We were fortunate to be hosted in the Malina family home: Frank Malina was an engineer at NASA and an artist. Many of his pieces were painting overlapping lights with different levels that moved, rotated to create complex sequence of colour. Roger Malina commented on how the aesthetic of the music merged well with his father's paintings.
The piece had been called Dream of a Debauched Dodo, I should dig up a cassette from the archive. At the gentle insistence from Doug - who understood the audience better than I did - I temporarily used the title Music for Didgeridoo and Electronics.