19EDO

19-EDO is a system of musical tuning that divides the octave into 19 equal parts. In this temperament, the octave is partitioned into 19 steps, with each step measuring 1200/19 ≈ 63.16 cents. Consequently, there are 19 distinct pitch classes within one octave, and the cycle repeats after 19 steps.

As an equal temperament, 19-EDO provides uniform spacing between consecutive pitches. This yields a richer palette of pitches than the standard 12-tone system, while preserving the familiar concept of a repeating octave. Certain intervals of just intonation are approximated by fixed numbers of steps; for example, a major third (justly about 386.31 cents) is approximated by 6 steps (approximately 378.95 cents), and a perfect fifth (justly about 701.96 cents) is approximated by 11 steps (approximately 694.74 cents). The octave remains exact, spanning 19 steps and equaling 1200 cents.

Usage and context: 19-EDO is one of several microtonal equal temperaments explored in contemporary tuning theory and electronic/computer music. It is often studied for its balance between a higher density of pitches and retainment of octave equivalence, making it useful for experimental composition and tuning research. Implementations appear in digital audio workstations, software tuners, and custom keyboard layouts designed to render 19 distinct pitch classes within an octave.

See also: other equal temperaments such as 12-EDO, 31-EDO, and broader microtonal tuning practices.