Chromatic scale

Musical scale set of twelve pitches

In Western music, a chromatic scale (or twelve-tone scale) is a set of twelve pitches within an octave, where the interval between any two adjacent notes is a semitone. The chromatic scale is a common layout of pitches for fixed-pitch instruments such as the piano and guitar, which are called chromatic instruments. Other instruments capable of continuously variable pitch, such as the trombone and violin, can also produce microtones, or intervals smaller than a semitone.

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