Involution is an attempt to fuse two very different sound worlds: that of the Kurdish Erbane (a type of traditional frame drum fitted with metallic rings), and concert Flute. In order to tease out the timbral character of the Erbane and avoid the obvious musical expectations of combining a western melodic instrument with a non-western rhythmic one, the normal roles of the two instruments are reversed: The flute plays a series of percussive gestures inspired by the rhythms and playing techniques of the Erbane, while the Erbane takes on a melodic role that emphasises its inherent resonances. Extended playing techniques enhanced by realtime harmonisation and granulation produce a series of harmonic and melodic figures that extent and blur the spectral boundaries between the two instruments.