Chromatic chord

Chromaticism is a compositional technique interspersing the primary diatonic pitches and chords with other pitches of the chromatic scale. Chromaticism is in contrast or addition to tonality or diatonicism (the major and minor scales). Chromatic elements are considered "elaborations of or substitutions for diatonic scale members".

Chromaticism is almost by definition an alteration of, an interpolation in or deviation from this basic diatonic organization.

As tonality began to expand during the last half of the nineteenth century, with new combinations of chords, keys and harmonies being tried, the chromatic scale and chromaticism became more widely used, especially in the works of Richard Wagner, such as the opera "Tristan und Isolde". Increased chromaticism is often cited as one of the main causes or signs of the "break down" of tonality, in the form of increased importance or use of:

As tonal harmony continued to widen and even break down, the chromatic scale became the basis of modern music written using the twelve-tone technique, a tone row being a specific ordering or series of the chromatic scale, and later serialism. Though these styles/methods continue to (re)incorporate tonality or tonal elements, often the trends that led to these methods were abandoned, such as modulation.

David Cope describes three forms of chromaticism: modulation, borrowed chords from secondary keys, and chromatic chords such as augmented sixth chords.

The total chromatic is the collection of all twelve equally tempered pitch classes of the chromatic scale.

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