What is a Quartal Harmony?

Quartal harmony is a type of harmony in which chords are built by stacking intervals of fourths instead of the traditional thirds used in most Western chord structures. In standard harmony, chords are usually formed by stacking thirds (for example, C–E–G). In quartal harmony, the notes are arranged in fourths, such as C–F–B♭.

This method of building chords creates a more open, ambiguous sound compared to traditional triads. Because the intervals are different from the typical major and minor chord structures, quartal chords often sound modern, spacious, and less clearly tied to a specific tonal function.

Quartal harmony is commonly used in jazz, modern classical music, and film scores. It became especially prominent in jazz during the mid-20th century, where musicians used stacked fourths to create fresh harmonic textures and support modal improvisation. The technique is often associated with modern and experimental harmonic styles.