Abstract:

In using electronic music synthesis for performance, an important issue is providing the musician with a familiar and powerful way of controlling the instrument. Keyboards have been the most common control device, but the keyboard is limited in expressive possibilities compared to other instruments such as the guitar. We are developing an electronic instrument which uses the electric guitar as a performer interface which controls a wide palette of sounds and special effects.

We use a special guitar that is fitted with a fret scanning system and with separate magnetic pickups on each string. These inputs are processed digitally to analyze the guitarist's musical gestures. Several parameters are calculated for each string in real time and passed to a synthesis engine which plays sampled sounds and applies controllable modifications to the samples.

In another mode of operation, the actual signals from the guitar strings are modified by combinations of basic algorithms such as non-linear distortion, pitch shifting, and tuneable filtering.

This instrument incorporates a new digital protocol for communicating music performance data, called ZIPI. This protocol has features lacking in MIDI, including real-time updating of information for individual notes.