The Méta-Intrument

The orchestra man

The Meta instrument is computer assisted music instrument. Three backward compatible prototypes were developed in the years 1989, 1996, and 2004. Its technology required developments in the field of electronics, programming, mechanics and aspects specific to the field of music. The MI3 is a high precision analyzer of human gestures. It is a mobile high-end human-machine interface that introduces the interpretation of complex gestures close to those of a conductor.

54 precise gestures

The MI3 can be imagined as a portable double joystick that can operate seamlessly 54 variables independently from each other. The position of the forearm is measured independently from the hands, the orientation of the rotary handles controls it's values independently from the palm of the hands and every finger features five independent sensors. The measurements of rotation are precise to one 20th of an angular degree and the measurements of pressure are exact to a 10th of a Gramm. 54 analogue sensors – placed at the heights of the elbows, the wrists and the fingers are linked to an Ethernet interface with a sampling conversion of 16 Bit depth 500 times per second with the wired version and 100 times per second in the wireless model (64 channel custom version of Ircam Ethersense Sensors Digitizer)). The very precise measurements of position and pressure allow calculating speed, acceleration and directions for each sensor.

Regarding the backpressure

The aspect of backpressure has been particularly taken care of. The friction and the reset force of all swivel-joints (at arm and wrist) can be regulated. Furthermore the foam-buttons are constructed softly and work without any offset to allow a strictly linear and complete measurement of the pressure. The MI3 is connected to a microcomputer where gestural information is used either by specialized programs like Max/MSP (© Cycling IRCAM), Pure Data, by applications like Reactor, Live,… or even by traditional programming languages like C++.

An exchange network

150 programs have been created for the Meta-Instrument (Serge de Laubier, Francis Faber, Mathieu Constant, György Kurtág, Bernard Parmegiani, Pierrre Sauvageot…). Those programs link the gestures of the musician to the processes of audio-manipulation as well as to lightning control, generation of computer graphics and manipulation of remote controlled mechanism.

György Kurtág Jr.