_derivations: improvisation for tenor saxophone and interactive performance system

_derivations is an interactive performance system for use by a solo instrumentalist, and is designed to derive its sonic responses to improvisational input from the instrumentalist's live performance. Conceived of as an autonomous performance partner, indirectly influenced rather than directly controlled by the performer, musical interaction with _derivations is achieved through a 'hands-free' mode of instrumental interaction with technology (i.e. human and machine communicate through sound only). A form of timbral matching is used to relate the most recent performance state of the instrumentalist to an expanding database of recorded and analysed performer phrases. The system makes direct use of these recorded phrases as sonic and gestural source material for transformation, extrapolation and recombination via its linked synthesis and processing modules. Recent advances in the system design enable the performer to merge a variety of pre-recorded and analysed 'session files' together, giving flexibility to the performer in defining aspects of the system's overall sonic vocabulary prior to performance. This aspect of the system design privileges the cumulative nature of the rehearsal/practice space, which forms an integral part of the system's interactive capabilities. This current performance is for solo tenor saxophone with _derivations diffused in 8-channel surround sound.