Present Perfect

I wrote this piece for cellist Matt Barley who wanted an opportunity to perform with my live electronics. The electronics are designed to enable a dialogue between the performer and an ‘electronic counterpart’. At the heart of this dialogue is mutual listening. Machine listening techniques turn the performers sound into musical data. This data is used to shape the responses generated by the computer. The performer listens to these generated sounds and responds, guided by the score. The electronics for the piece, programmed in Supercollider, contains several processes which combine internal musical-logic defined algorithmically with the data extracted from the performer’s playing. Pitch, rhythm, and some timbral properties are extracted from the cello playing. These then control synthesis and sound processing parameters by way of decision making in the electronic processes. For example the computer may react selectively just to long notes by synthesising matching sounds. In other cases it may processes high and low sounds differently. The results are dynamic processes which sometimes correspond to the type of music the player is performing and sometimes counteract them. But ultimately, this is still a solo piece – the player turns these processes on and off through the use of a set of pedals.