for trombone and digital processing, 2011, duration 11:50
My electronic works have generally been composed in the traditional "instrument and tape" format which, given the timing inflexibility of the tape, compromises the player. Ghosts of Sackbut is one of a series of pieces in which I have begun to compose for " acoustic instrument and computer music." The computer will listen to the notes the performer plays or how loud the note was played and then respond according to my instructions. This creates a situation in which the performer has control over the events of the piece by his/her musical gestures.
Ghosts of Sackbut is an interactive work for trombone and interactive sounds. In this case the computer processes the sounds of the trombone to create sonic copies that are pitch shifted, time shifted, and/or timbrally shifted. Among the specific DSP modules are a dual delay unit, which allows two simultaneous but independently controllable echoes, four independent audio recorder/players, and a quad pitch shifter that can create chords, as well as granulation modulation modules that create real-time control of modulation frequency and depth.
Although most parameters of the piece are precisely controlled and notated, there is no metric pulse. Instead there is considerable freedom for the performer to “time” events according to expressive and emotional involvement of the performance.
Haim Avistur, trombone