"Chromata" is an exceptional series of pieces of electronic music in the sense that a parameter is put to the foreground that in electronic music usually is not: namely pitch.

In "Chroma 1", two parallel pitch structures are audible. One structure is presented on a loudspeaker in front of the audience, the other on the loudspeakers surrounding it. Both are based on the same twelve-tone row based on perfect and augmented fourth intervals. The two pitch structures complement each other in such a way that at various moments in the piece (articulated by a low pitched sound) all chromatic notes within a range of two octaves are used. The pitch structure of the piece was completely defined on forehand; all other parameters such as durations, timbres, dynamics and so on were freely interpreted during the actual production of the piece with one goal only: to make the pitch structure as clear as possible.

The sounds on the front speaker are instrumental and vocal sounds, which underwent transformations in the frequency domain. The sounds on the surround speakers are exclusively derived from vocal material. There, a large number of transformations is produced for the whole structure of 12 minutes. Which surrounding transformation is unveiled at which time section could be worked out differently, resulting in form variants based on the same pitch structure. "Chroma 2" was produced with this idea in mind: to produce a variant of the piece by systematically permutating the form of the surrounding structure while leaving the pitch rows in tact. Finally, the pitch structure on the center speaker was left out of the piece completely, being there only as something to be remembered from listening to "Chroma 1". The emptyness caused by the missing structure to me has the effect of a "black hole" with a strong gravitational force.

"Chroma 1" was commissioned by the Fonds voor de Scheppende Toonkunst.