Dolores Catherino


musician, composer, researcher, sound explorer

Why has visual technology rapidly evolved from display resolutions of 720p to 4K and beyond, while audio technology remains relatively stagnant?

Current 12-bit color depth can provide over 68 billion colors. In contrast, audio streaming services provide less than CD quality. And the CD format itself is over 30 years old. Many other aspects of audio technology have remained sluggish to change: the MIDI protocol (1983), the chromatic keyboard (1361), and frequency bandwidth limits in audio technology which remove all harmonic content of a complex sound beyond 15-20 KHz.

Is there an assumption that we have already reached the limits of audio perception? My practice with PolyChromatic Music explores this question.

This site is intended as a ‘field journal’ of my explorations with polychromatic music and pitch-color. I hope it inspires you to pursue new directions and perspectives in your own creative practice.

Music has always been a blend of art, science and technology for me. The many years of practice with different mechanical-era instruments provided a foundation and diverse perspectives for approaching new music technology.

I am fascinated by the uncharted potential of auditory perception in art and science. Music can lead the way in expanding our sonic awareness and scientific understanding of hearing, psychoacoustics and sound vibration perception beyond the ears: active/passive touch, bone conduction, etc. Increasingly refined pitch discrimination can expand aesthetic awareness and reveal new expressive possibilities in the musical and sound arts.

As an musician, my aesthetic orientation comes from Romantic ideals of art: hope, striving, transcendence, passion, intuition, humanism. These ideals are important in a time of far-reaching standardization and technological simulation of human action and thought. I hope that my compositions challenge the listener perceptually, emotionally and aesthetically.

While I enjoy minimalism as a listener, my compositions have an opposite tendency of expressing a continuum of structural change and using repetition as a minor element. The musical ideas are expressed primarily through a direct intention of the musician. This is in contrast to the use of technological, theoretical or random processes for generating primary musical content, with added human creative arrangement and editing. In practice, music creation within our technological-era exists along a spectrum between these extremes of composing and compositing.

All of these different creative orientations open ever-expanding, unique worlds of musical possibility. And each of these musical orientations can express levels of complexity that could fill a lifetime of practice. This wide divergence in musical practice seems to mirror an era of constant change, emerging cultural perspectives and eroding traditions.

Music is similar to any language in its ability to express ideas, intelligence and emotion. In this sense, the enduring value of music comes from the depth of expression and the interaction of these qualities with the listener. In this way, the music grows with the listener and the listener grows with the music.

We live in a time of increasing uncertainty, transience and instability. I try to express this spirit of the times – the ideas, hopes and fears – within a context of known musical relationships. The result is music that sounds radically different and yet familiar. Using a chromatic perspective allows the listener to experience new dimensions of micro-pitch sound and harmonic interaction through contrast and combination. This becomes a point of departure toward diverse (non-chromatic) musical systems of the future. Evolution of musical systems expand the expressive limits of ideas, aesthetic qualities and nuance in sound.

In contrast to works of contemporary classical music, which are oriented toward an evolution of musical structures of the past (past-present), my polychromatic compositions express an orientation in the future – imaginatively looking back toward the present and creating a ‘bridge’ in between (future-present).

Exploring the leading edge of musical possibilities presents frequent technological challenges. Time is often inefficiently diverted to inventing workarounds to the limitations of music software, hardware, audio/midi protocols, etc. I suppose that every generation of artists has to overcome the limitations of its tools. The ideas of the human imagination and intuition can exceed all conventional means to express them. This creative tension may facilitate further evolution of the tools.

In expressing concepts of polychromatic music and pitch-color, it important to look at some of the fundamental ambiguities in musical language.

Tone describes a perceptual and conceptual focus on the composite of a fundamental pitch and its harmonics (a spectral identity; tone color; timbre).

Pitch describes a perceptual and conceptual focus on a fundamental pitch only (a frequency identity; a pitch-color).

Terminology: Associations and Relationships

Note describes:

  • A synonym for tone or pitch.
  • An association of a physical location (i.e. key, fret, fingering) on an instrument with a pitch (a location identity).
  • A notated association of a pitch with a visual location on a staff or grid (a location identity).
  • An association of an electronic switch (key, knob, pad) with a number (MIDI note number; a protocol identity).
  • In association with rhythm and time duration (half note, quarter note; a temporal identity).

Tonality describes several different aspects of musical practice:

  • In relationship to a key center (tonic, tonal), multiple key centers (polytonal) or no key center (atonal, twelve-tone).
  • As an intervallic relationship (semitone, whole tone, tritone).
  • As a harmonic relationship (overtone, subtone).
  • An association with micro-pitch (microtone, quarter tone) scales and music created with them (microtonality).

In the 1970’s, Ligeti created the term micropolyphony, to describe the chromatic, polyphonic musical textures he created in his works.

With the above distinctions in mind, micropolyphony can be more precisely described as microtonality in that uses chromatic tone cluster harmony (semitone derived intervals), perceived as a composite of (spectral; timbral) tone colors, rather than as a distinct structure of harmony (chord, harmonic progression). This type of chromatic, tone cluster harmony extends possibilities for the exploration of new forms of ‘tonality’ – beyond the functional harmony of earlier musical eras.

Micropitch describes divisions of the pitch continuum into intervals of less than a semitone (100 cents).

Harmonic describes several different aspects of musical practice:

  • The relationship of interval combinations (harmony; polyphony; harmonic/chordal structures).
  • The embedded harmonics within a pitch or tone (overtones, harmonics, sound spectra).

Polychromatic describes a system of representing any micro-pitch division method (ET, EDO, JI, MOS. etc) in a unifying notated language, using concepts of pitch-color and interval-color to intuitively express the exponentially expanded musical possibilities that these scales provide.

In Tune/Out of Tune describes the coarse perception of a mismatch between a pitch and its sounded or implied harmonic context.

Sharp/Flat describes both pitch definitions (Bb, A#) and pitch modifiers (accidentals; b, bb, #, x). This seems to be a primary reason why the use of  the monochromatic system for expressing micro-pitch scales has become cumbersome and inefficient. Each micro-pitch scale method results in different, incompatible pitch modifier symbols limited by black and white notation.

Pitch-color describes an awareness of distinct variants of each chromatic pitch. Micro-pitch scales can be anchored in memory with the practice of intuitive pitch-color associations (i.e. color spectrum ordering). Pitch-color creates a distinct micro-pitch concept (pitch identity) to accompany refined perceptual discrimination. It also describes a harmonic component of tone color/timbre: part of a spectral composite of harmonics creating a sound quality (sound identity) of the pitch, i.e. flute-like, brass-like, light/heavy, coarse/smooth, bright/dark.

With these distinctions in mind, we can explore more of the creative possibilities within polychromatic music.

Polychromatic Music

Information, video performances, audio and scores