These two short piano pieces are a first "test flight" of a new "quad variable-length step sequencers with meta-sequencer" module that I've designed and coded with Max8 as part of a project to produce a Max-based software synthesizer that supports the composition and improvisation of poly-microtonal, poly-tempic music.
In these pieces the sounds are produced by Pianoteq 6, using a Steinway D piano model. The quad step sequencers drive four instantiations of the Steinway using MIDI, each playing a one note at a time melodic sequence. The sequencers can each be configured to play a sequence of variable length, so for example, one sequencer might be a 48 note sequence, another a 72 note sequence, a third a 60 note sequence, and the forth a 32 note sequence. Each sequencer can be configured to run at a different tempo, so the resulting rhythmic texture can be quite complex. Or simple. A "meta-sequencer" that is closer in design to a "score reader" controls their tempi, and other parameters.
In addition to these capabilities, each sequencer's material can be transformed on the fly by either the meta-score or manually by the performer. One can transpose the material, rotate different parts or all of the material, reverse different parts or all of the material, sort different parts of the material, producing ascending or descending sub-sequences, and deform or transform the material in various other ways.
The score can control the "global tempo", causing group accelerations and decelerations, or this can be done manually. The score itself can be made to run faster or slower either manually or through the score.
Although the module is being used in these two test flights to drive MIDI, it has the capability to drive the various oscillators, filters, random sources, etc. that the final synthesizer design will contain.
In these pieces, the pitch material is a 12-tone scale derived from 22 EDO, known as Erlich's hexachordal scale, but the module has the capability to deal with and display pitch space in any number of divisions.
Finally, the material used in the sequences can be generated by statistical processes, using pitch-class transition probability tables. This is how the melodic material was created for these pieces. In this case, the two probability transition tables used, favored four pentatonic scales: two pelog scales, and two slendro scales. One probability table was "strict," in that it only allowed the transition from one scale to another at "common tones" shared by both scales, the other one was "relaxed," in that it allowed movement from one scale to another by step-wise chromatic motion.
Both pieces were performed live by myself and the meta-sequencer working in tandem. No editing was done.