Bartholomäus Traubeck is a German artist whose piece ‘Years’ uses tree-ring data to create music, using a turntable to play a slice of wood as if it were a record. The patterns and textures drawn as rings in the cross sections of trees visually represent sometimes hundreds of years of growth in a single disc-shaped object, something which Traubeck found intriguing. His next thought was to turn these visual compositions into audible compositions, to produce pieces that compressed decades of time into a musical composition of just a few minutes length.
“There is a small, very fast camera mounted on the tonearm of the device. It reads the rings as they pass the camera, determining if the ring grows or shrinks in that certain area and how fast it does that,” Traubeck said. “It also registers the thickness of the rings over time as well as cracks or other irregularities in the wood.”
This data is then mapped to the 88 keys of a piano, with the thickness representing the velocity of the notes played and the growth factor representing the position of the note in the scale. What you then get from the machine are MIDI notes which are played via a piano sample plug-in.
“The technological part was definitely a challenge,” Traubeck recalls. “To get the machine and its movements just right in order to have a clean image feed from the camera wasn’t easy. What proved to be infinitely more difficult than I first assumed was obtaining the cross cut slices of wood. I started out with cutting and sanding down wood that was stored for five years or longer but it constantly cracked, sometimes immediately, sometimes after a few days or weeks.”
Some types of wood worked better for Traubeck, some did not work at all. Since he did not want to be limited to certain kinds of hard, durable wood, Traubeck had to find another way to produce these discs. The answer to his problem was to turn to using cross-cut veneer. “I worked together with a big veneer company in Upper Austria to get the perfect slices,” he said. “They are now about 1mm thick or less, mounted to a plastic sheet with a special glue, and then again mounted on an acrylic disc of about 8mm thickness to stabilise.”
Traubeck explained how every single slice will play a
different composition. The
differences between two slices of oak might range from very little to clearly audible, depending on how and where the oak grew, but the differences between different kinds of woods are always very strong. “This is why I tend to use slices from different kinds of trees such as alder, ash, birch, fir and spruce for the exhibitions,”he said. “The listeners can then really differentiate between the slices, which makes it more interesting to listen to more than just one.”
Traubeck has just finished a piece he’d been working on for quite some time called ‘Two Axes In A Forest (Resonanz1)’ which consists of two guitars playing each other through transducers. “The sound of one guitar is induced into the other, making the strings of the other guitar vibrate. This vibration is transformed into a sound signal by the pickup and sent back to the first guitar via an amplifier.” Traubeck explained. “Thus an endless feedback loop is being generated, which in a perfect world might achieve a state of perfect resonance between the two guitars. But since these industrially produced objects are not 100% the same and fluctuations in air pressure and other sounds from the outside influence the system, the frequencies never match exactly and an endless composition of drone sounds is being generated.”
Traubeck’s next project will again revolve around sonification of natural processes, namely evolution, but it is still in such an early stage that no details are being given away just yet, so keep your eyes peeled.