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Prix 1987 - 2007

ORF Oberösterreich

Peter Bosch, Simone Simons

In "Krachtgever" by Peter Bosch and Simone Simons, forced and natural frequencies of objects are so attuned to each other that the movements and sounds created by the installation can change almost imperceptibly from order into chaos and vice versa.

"In 1896 Nikola Tesla, one of the greatest geniuses of the electrical age, strapped a small oscillation motor to the central beam in his Manhattan laboratory and built a powerful physical resonance that was conducted through the building and into the earth causing an earth quake in which buildings shook, panes of glass broke and steam pipes ruptured over a twelve block area. He was forced to stop the motor with a blow from a sledge hammer. Tesla stated that he could calculate the resonant frequency of the earth and set off a strong vibration with a properly tuned driver of adequate size and specific placement."

(from: "The sound of one line scanning" by Bill Viola, in "Sound by Artists", Walter Phillips Gallery, Banff, Canada, 1990, p. 43)

This supposition was the take-off point for the "Krachtgever". While working on the theme "Resonances stimulated by mechanical vibrations" our main interest was not to amplify just one existing frequency, but to create a complex system in which various frequencies influence each other. This is done to induce unstable balances which the slightest change could disturb enough to produce an unpredictable outcome. Forced and natural frequencies of objects are so attuned to each other that the movements and sounds created by the installation can change almost imperceptibly from order into chaos and vice versa. The role of the computer is paradoxical: although it has power over the mechanics (electro-motors), it can only partly foresee the physical outcome of ist decisions. In addition to unstable balances and order and chaos, another element is sound. The pure power of sound and the pure existence of manifest sound (music) remains an integral part of an our installations. The medium sound gives power over a specific place, it occupies that space: The Krachtgever permits us to generate vibrations with which we can fill the space. After all, sound waves are vibrations.

The Krachtgever ("Invigorator") consists of a minimum of seven, maximum fourteen 2.50 metres high stacks of four wooden boxes each, with a total width of 6 to 12 metres. The boxes are joined together with metal springs, both horizontally and vertically. One oscillating motor is attached to each stack. These motors are driven by a computer that, by varying the speed at which the motors rotate, causes interesting interferences between the stimulated vibratory and resonant frequencies of the construction. Depending on the combination of selected motors and frequencies, each box can be vibrated independently, while one complete stack may also be brought into one periodical movement. Also combinations of vibrations can be generated to occur simultaneously at different positions within the system. Each box contains different materials. These "rattles", varying in volume, weight and sound, posses their own resonating characteristics. When stimulated by an oscillation motor, the combined vibrations from all the elements - the springs, the boxes, the various rattles in the boxes, etc. - produce an extraordinarily complex whole. In spite of this complexity, the relationship between all the visual and aural elements of the installation is unambigious. The sounds are pure, unamplified and rich in detail. The repertoire of the Krachtgever can be best described as stacks of sound varying in strength, timbre and rhythm from the subtle to the powerful, from the ordered to the chaotic.

A computer controls the frequencies of oscillating motors by sending MIDI-information to a MIDI-to-CV converter. The computer program is a structure divided into a set of "musical phrases". It can choose only one phrase at a time. A phrase simply consists of three variables:

1. Which of the seven to fourteen motors take part in the phrase?
2. Start and end frequencies for each motor used in the phrase.
3. Total time used while going gradually from start to end frequencies.

Combinations of motors are fixed in some phrases, in others the computer chooses motors at random. The elapse in time of the motor frequencies can be synchronous or asynchronous, also depending on the chosen phrase. There are a kind of preset-phrases, in which almost everything is fixed, while others are definied rather freely. They are divided into three catagories: quiet, medium and rough (loud) behaviours. The memory of the program does not go back further then one phrase. When it starts a new phrase it will never choose one within the same category as the one to which its predecessor belonged. This procedure forms the base of the typical free and dynamic development of the Krachtgever’s sound at the macro-level. The physically extraordinarily complex properties of the construction itself garantee an even less predictable texture at the micro-level: here too, the future is influenced by the past. A strong resonance of a certain box (or boxes) does not die out at once and will therefore influence the outcome of a following "phrase". This means that the same phrase can sound completely different, depending on the phrase played before, etc. Another artistic tool that is used in every performance is the adaptation of the work to spatial and acoustic circumstances. We can change both the number and contents of the boxes (the "rattles") and we always change details of the software on the spot. Although the duration of the software is indefinite, the installation itself does not work continuously. We usually use a sensor to switch it on, once the public has entered the space.

The development of the Krachtgever was made possible partly by a grant of the Fonds voor Beeldende Kunsten, Vormgeving en Bowkunst, Amsterdam.