The earth's atmosphere is alive with electromagnetic activity at the low end of the radio spectrum, Most comes from lightening storms across the globe, although some of the most beautiful forms are generated by the interaction of solar winds with the magnetosphere.
I say "beautiful" forms, because with a Very Low Frequency (VLF) receiver, you can pick up this electromagnetic activity and reproduce an equivalent sound. Check out the NASA page for streaming 'sferics' . The available sounds are like bird song, animal calls or deep breathing. With some pretty good electronics skills, I could make a receiver myself. With passable skills, I could probably put together one of the available kits. Since I have neither, I'm deeply grateful to Steve McGreevey and his website Auroral Chorus. In addition to providing a great introduction to the subject, the site also includes many examples from his own field recordings. And most important, he sells completed and tested VLF receivers. One of which I have on order.
I'm going to start working out a piece that I first started thinking about over 5 years ago. Called Voices of the Noosphere, it is a piece for radio telescope and didgeridoo. The idea was that the telescope would be receiving electromagnetic signals from a pulsar. That pulsar signal would be represented in sound. I had a patch written in the cSound software language that would apply the envelope of my didgeridoo playing to the 'sound' of the pulsar. I'd throw in some optional granular synthesis processing for aesthetic effect, and then re-broadcast the signal out to the stars.
If I remember right, the very first impulse for this came as part of a discussion of SETI message construction with Doug Vakoch. We'd met at a SETI workshop, and started to write down a proposed structure for an outbound message, one that attempted to encode notions of 'creativity'. We did this by presenting material that was shaped by the fibonacci series. Rhythmic bursts of radio at specific frequencies, harmonic relationships across the radio spectrum: all governed by the Fibonacci series.
The idea was that a receiving culture would identify the underlying series, and then would recognize that other parts of the message manipulated this underlying pattern. A natural source - like a pulsar - could create a repeating pattern, but it is highly unlikely that a natural source would move through the first 5 numbers of a Fibonacci sequence, and then retrograde that pattern.
I thought that a larger piece could be done using an identifiable radio source - like a pulsar. The electronically manipulated sound along with my didgeridoo would provide a couple layers of counterpoint. A receiving culture could identify the pulsar, and then ask themselves what on earth that other material represented. I like the didgeridoo for this because of all instruments, it seems to create music with a period about as long as a human breath, with overtones that seem to resonate with the human heartbeat.
Another element of the piece was that this same material would be meaningful for a human audience, listening to the sonic representation of it all. The sound becomes an interstitial space, a place where the biological necessity of sense perception overlaps with a representation of the larger electromagnetic form of the universe. This is a privileged location, one that is liturgical, poetic, alchemical.
I've gotten a lot of mileage out of this piece, for something that has never been realised. With the VLF receiver, I'm going to start working out the details, and creating the alchemical conjunction. I may not (yet) be working with pulsars, but I will be interacting with the electromagnetic spectrum in a meaningful manner.