andrew.aday (at) columbia.edu
Two Pages was one of Glass’s first experiments with additive and subtractive procedure–there is no harmonic structure, only a single 5-note motif which is spliced, added, and subtracted upon. Melody and rhythm coalesce into one, such that upon listening one hears the additive and subtractive procedures themselves, operating upon a nucleus of sound and permuting it into something whole, organic. With this piece and the few others composed during the same period (Music in Fifths, Music in Contrary Motion, Music in Similar Motion), a new language of music was conceived.
In this electronic arrangement I replicate in timbre the processes Glass applied to his motivic pitch material. In general, what this means is that when additive procedures are in play, harmonic overtones are added to the sonority, and when subtractive procedures are in play, such overtones are removed. The sound itself grows in complexity or simplicity parallel to the expanding and contracting motivic line. Modular synthesis affords an incredible amount of sonic liberty, so it seemed the natural medium of choice.
The piece is divided into 5 parts, and in each part I experiment with a different way of warping the sound:
Beginning with a sine wave, 5ths and octaves are added above and below the fundamental. Attack is adjusted according to the register of the partials.
A sine wave is modulated and phase shifted to add harmonic content, then run through a Moog-inspired ladder filter. CV modulation on filter cutoff, drive, and resonance.
(Psychoacoustics) Two slightly different plucked timbres pass the “melody” back and forth in a kind of timbral hocket. These two voices are also increasingly panned. The ear is unable to hear the original melody intact, and two new melodies are born.
(Psychoacoustics) A pitched kick drum module gradually transforms into static noise. The noise is not pitched, but from sheer repetition I noticed my “inner ear” was hearing the melodic pitches in the noise, as if it had been conditioned into acting as a comb filter.
Finale. Randomized filter cutoffs, wavetable synthesis, FM synthesis, detuned saw wave lead, and use of de-synced high-pass + low-pass + band-pass filters in tandem.
My first project in ChucK. A ChucK program sequences MIDI data and orchestrates when each virtual player moves onto the next pattern (The probability a player repeats a pattern or moves on is determined by a logistic function, weighted according to the length of the pattern). Source code