Quartal

Quartal is a term with multiple related meanings in music, language, and business. In music theory, quartal harmony refers to chords and textures built primarily from intervals of a fourth, rather than the traditional triadic practice of thirds. A simple quartal sonority can be formed by stacking fourths, for example C–F–Bb or F–Bb–Eb. Such chords sound open and ambiguous about a tonal center, and they are often used for coloristic or modernist effects. Quartal harmony can appear in isolation or as part of larger tonal landscapes, sometimes alongside more conventional materials.

In practice, quartal writing emphasizes symmetry and parallel movement and has been used in both classical and jazz contexts. Early 20th-century composers and modernist improvisers experimented with fourth-based sonorities, while in jazz, pianists and instrumentalists adopted quartal voicings as a core element of modal and post-bop harmony. Notable practitioners include McCoy Tyner, whose quartal voicings helped shape a distinctive sound in jazz harmony, and other musicians who explored non-triadic textures within different genres.

In German-language usage, Quartal more often means a quarter of a year or something occurring every quarter. As a noun, it denotes one of four equal periods in a year; as an adjective, quartal can mean quarterly or per quarter. The term appears in business and finance in phrases such as Quartalszahlen (quarterly results) or Quartalsbericht (quarterly report).

Overall, Quartal denotes both a specific musical technique of building harmony in fourths and, in German, a time-based or periodic sense relating to quarters.