quadruplum

Quadruplum is a term in medieval music theory describing the fourth melodic line in polyphonic vocal music. The name comes from Latin quadruplum, meaning fourfold, and it denotes the presence of a fourth voice in textures that also include a cantus firmus or tenor, duplum, and triplum.

Origin and use: The concept developed as polyphony expanded beyond two and three voices. By the late 13th and early 14th centuries, some motets and other polyphonic works from the Notre Dame school and the Ars Nova tradition employed four distinct voices. The quadruplum typically occupied the uppermost register, providing a separate melodic line that interacts with the lower voices.

Notational practice and interaction: The quadruplum shares independence with the other voices and is notated within the same multis voice framework. It operates alongside the cantus firmus, duplum, and triplum, with combinations of melodic contour, rhythmic activity, and text setting that contribute to overall texture. Dissonance, concord, and melodic parallelism are managed according to the conventions of the period.

Repertoire and significance: In late medieval polyphony, four-voice textures appeared in motets and related forms, reflecting increasing melodic and rhythmic complexity. The term quadruplum is primarily a analytic designation used by modern scholars; not all four-voice pieces were explicitly described as having a dedicated quadruplum, and usage can vary by theorist and edition.

See also: Duplum, Triplum, Cantus firmus, Motet, Ars Nova, Notre Dame polyphony.