Chromatic fourth

For Chromatic tetrachord, see Chromatic genus.

In music, a chromatic fourth, or passus duriusculus^[1], is a melody or melodic fragment spanning a perfect fourth with all or almost all chromatic intervals filled in (chromatic line). The quintessential example is in D minor with the tonic and dominant notes as boundaries,  Play (help·info):

The chromatic fourth was first used in the madrigals of the 16th Century.^{[citation needed]} The Latin term itself ("suffered somewhat hard") originates in Christoph Bernhard's 17th century Tractatus compositionis augmentatus (1648-49), where it appears to refer to repeated melodic motion by semitone creating consecutive semitones.^[1] The term may also relate to the pianto associated with weeping.^[1] In the Baroque, Johann Sebastian Bach used it in his choral as well as his instrumental music, in the Well-Tempered Clavier, for example (the chromatic fourth is indicated by a red bracket),  Play (help·info):

In operas of the Baroque and Classical, the chromatic fourth was often used in the bass and for woeful arias, often being called a "lament bass". In the penultimate pages of the first movement of Beethoven's Ninth Symphony, the repetitions of the chromatic fourth in the cellos and basses stir up a sense of inevitable tragedy.^{[citation needed]}

Lament bass from Vivaldi's motet "O qui coeli terraeque serenitas" RV 631, Aria No. 2^[2]  Play (help·info).

This doesn't mean that the chromatic fourth was always used in a sorrowful or foreboding way, or that the boundaries should always be the tonic and dominant notes. One counterexample comes from the Minuet of Wolfgang Amadeus Mozart's String Quartet in G major, K. 387 (the chromatic fourths are conveniently bracketed by the slurs and set apart with note-to-note dynamics changes),  Play (help·info):

Musical works using the chromatic fourth or passus duriusculus

• "Dido's Lament"^[1]

Sources

1. ^ ^{a b c d} Monelle, Raymond (2000). The Sense of Music: Semiotic Essays, p.73. ISBN 9780691057163.
2. ^ Williams, Peter (1998). The Chromatic Fourth: During Four Centuries of Music, p.69. Oxford University Press. ISBN 0198165633.