Close harmony

Close harmony places neighboring vocal parts relatively near one another in pitch, producing a compact arrangement of chord tones.

Chord voicing: The arrangement of notes from a chord among instruments or voices. Close harmony depends on how chord tones are assigned and spaced across vocal parts.
Barbershop music: A style of unaccompanied vocal music built around four-part harmony and ringing chords. Its quartet arrangements use tightly coordinated parts to create characteristic overtones.
Open harmony: Harmony whose neighboring parts are spaced relatively far apart. It is the direct spacing opposite of close harmony.
Musical interval: The measured distance in pitch between two musical notes. The intervals between adjacent parts determine whether their spacing is close.
Morten Lauridsen: An American composer known for choral works including O Magnum Mysterium and Lux Aeterna. His choral writing offers a modern concert-music context for compact vocal sonorities.
Voice leading: The movement of individual musical lines from one chord to another. Smooth movement between nearby notes helps vocal parts remain compact across chord changes.
Barbershop seventh chord: A barbershop chord formed by four voices sounding a dominant seventh chord in close, tuned relation. This sonority showcases the ringing effect of closely coordinated vocal parts.
Homophony: A musical texture in which voices or instruments move together in coordinated rhythms. Close harmony can use homophonic rhythm, but spacing alone does not determine texture.
Triad: A three-note chord built from a root, a third, and a fifth. Triads provide a basic three-part structure that voices can arrange compactly.
The Chordettes: An American female vocal quartet known for pop hits including Mr. Sandman and Lollipop. Their close vocal arrangements carried the sound into mid-century popular recordings.

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