Chromatic fourth


In music, a chromatic fourth, or passus duriusculus, is a melody or melodic fragment spanning a perfect fourth with all or almost all chromatic intervals filled in. The quintessential example is in D minor with the tonic and dominant notes as boundaries, :
The chromatic fourth was first used in the madrigals of the 16th Century. The Latin term itself—"harsh" or "difficult" "step" or "passage" —originates in Christoph Bernhard's 17th century Tractatus compositionis augmentatus, where it appears to refer to repeated melodic motion by semitone creating consecutive semitones. The term may also relate to the pianto associated with weeping. In the Baroque, Johann Sebastian Bach used it in his choral as well as his instrumental music, in the Well-Tempered Clavier, for example, :
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 chromatic fourth appears in the cellos and basses.
This does not 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, :

Musical works using the chromatic fourth or ''passus duriusculus''