| click
to view movie clip of a live performance of the 5.1-channel piece
At the heart of this piece is a genetic algorithm which makes
all musical decisions and realizes the score in real time. The
'note' is the fundamental organism of the system and is defined
by a genetic code which includes features such as amplitude, frequency,
envelope, pitch clarity, and shift rates. These attributes determine
how and when a note expresses itself, and also how a note behaves
in relation to is neighbors.
A hierarchical structure is also at work in the system wherein
notes belong to gestures, which belong to phrases, which in turn
belong to sections. These higher levels are defined by genetic
features such as density, central frequency, harmonicity, and
rhythmic activity. The genetic features of these higher levels
guide the broader course of the music relative to their position
in the architecture in much the same way that families, communities,
and nations influence their members.
click
to view movie clip the 2-channel piece
Depending on its genetic profile, a note can be realized in
one of two ways: as a filtered sample by the computer, or as a
note performed by a live performer. During the performance, the
percussionist sightreads and interprets a musical score from the
computer monitor which is generated in real time by the algorithm.
Using microphones placed around the performer, he or she can place
sounds in particular spatial locations that mimic and enhance the
diffusion of the computer generated sounds.
The form of this piece mimics the character of a percussion note such as a
cymbal crash. A burst of energy slowly dissipates into a sustained
resonance.
|
