Musique instrumentale d'ensemble (Ensemble instrumental mixte de 10 à 25 instruments)

Color Coordinate(s) is all about the joy of rhythmic polyphony and interplay. In part one, all the music is based on strict symmetrical isorhythmic procedures The main materials are ten rhythmic units that are introduced gradually as they overlap with each other in various ways. Each rhythmic set is mirrored in some way, creating ten perfectly non-retrogradable isorhythms. In other words, the second half of each rhythm is the exact reverse of the first, a signature technique of Messiaen. Some units even have multiple mirrors within mirrors. I devised three categories of these palindromic rhythms, with silences of varying lengths (or none at all) separating each half or whole statement of the rhythmic unit. The ten total rhythmic units are further related in five pairs, so that as they overlap, the listener will hear spirally wound strains of rhythms that imply continuity or development. Another perceptive challenge is the fact that the rhythms are presented at varying distances from one another, so that one becomes aware of time passing differently as new material gets added to the mix. Some of the units receive inverted canonic treatment by two voices at once, further complicating the texture. The rhythms are isorhythmic in that they are of fixed length and rhythmic order (talea) but their pitch content and related harmonies shift with each new presentation (color). This medieval procedure, beloved of the ars nova composers, is updated so that the term "color," previously suggesting only melodic content, is now applied to timbral variation as well, and appropriately enough!

The music in this first section was conceived with a very formalistic plan, but the materials were generated freely and "in the moment." New rhythms emerge out of old ones, like soloists in jazz improvisation who "trade fours," crossfading or referencing ideas and rhythmic schemes in passing which lead toward new directions that then get commented on in turn. Often this rhythmic dovetailing is serendipitous, with the new material as an offshoot or side-effect of something considered fleeting or subordinate in the first instance. This idea complements, in evolutionary biology, the idea of the spandrel, itself an architectural term.

A transition starts with some of the fragmentations left over at the end of part one, leading to a new section of irregular groove-based music with multiple layers and rhythms. The music in part two is not constructed with any of the kind of formal vigor of the preceding section, but its spirit is a kind of extension of it. Microtonal chord progressions anchor restless bass grooves and syncopated riffs. Strains of improvisatory post-bop/free jazz lines square off against upwardly-mobile basslines that multiply at every turn.Color Coordinate(s) is dedicated to the ever-inspiring spirit of Olivier Messiaen and his music.

Anthony Cheung, June 2009.