Groene Ruis – a performance for a sounding tree
Groene Ruis starts with a tree played like a small harp. The resulting sounds initially suggest that an electronic harp is being played. There is, of course, no acoustic constraint that causes the tree to sound like this, on the contrary, just plucking a tree without any electronic intervention would sound totally different. Seeing how the tree is plucked as well as hearing the result, there is a relationship between the visual and auditive aspects of the performance. This relationship is neither constrained by physical limits, as is the case with for example the violin, nor are its responses linear (a louder pluck does not create a louder sound and the height of the pitch is not triggered by the height of the branches). To create the sounds in this piece I use two small contact microphones in the tree, computer software (a MaxMSP patch) and four loudspeakers. Every time the tree is touched, the contact microphones transform the physical vibrations of the tree into electric current. This electric current is used by the computer as a trigger for playing a sound through the loudspeakers. The relationship between the gesture input and the sound output is therefore based on a minimal relationship; the sound of the tree when it is touched.
However, during the performance the relationship between gestures and sound changes. As the tree is caressed gently by the performer this generates a totally different sound. The direct amplification of the tree vibrations, picked up by the contact microphones, diffuse in different ways over the four loudspeakers to produce an amplified and spatialised sound of the tree. Whereas the sounds of the first example, playing the tree as a harp, have no physical relationship at all with the tree, this time there is a more physically constrained relationship, since it is the sound of the branches of the tree that are audible in a distorted form. The sound production method is therefore much closer to a traditional musical instrument since the instrument can be ‘played’ by changing several parameters instead of just triggering a sound: louder or faster caressing will result in a louder or faster sound. At the same time, both movements have different connections with music. Whereas the first kinds of movements refer to playing a musical instrument, since they are similar to playing a harp, the second kind of movement, caressing the tree, refers to a non-musical activity. An important compositional element is therefore the identity shift of the tree itself, due to a change in the way the tree is played by the performer.