SEQUENCE

in music, a melodic or chordal figure repeated at a new pitch, thus unifying and developing musical material. Real sequences are exact repetitions; tonal sequences are modified to conform to the key of the composition. In medieval music and literature the sequence was a Latin text and music sung at mass between the Alleluia and the Gospel. It developed about the 8th century from the trope (addition of music, text, or both) to the jubilus, the florid ending of the last syllable of the Alleluia. Sequences became highly popular throughout Europemost notably as an element of the Gregorian chantand thousands of examples of them survive that are appropriate to different liturgical feasts. Secular musical forms influenced by the sequence include the estampie (a dance) and the lai (a song genre of the trouvres, medieval French poet-composers). The melodic tropes originally added to the jubilus were normally broken into phrases that were repeated in performance (as aa, bb, cc, . . . ) by alternating choirs. Texts set to these and to Alleluia melodies were originally prose, hence the medieval Latin name prosa. By the 9th century the sequence developed a common poetic form that reflected the musical structure: typically, introductory and closing lines enclosed a series of rhymed, metrical couplets of varying lengths (x aa bb cc . . . y). Each syllable was set to a single note of music. Eventually, texts were set to newly composed melodies, and the lengths of the couplets were equalized. In the 16th century the Council of Trent removed all but four sequences from the liturgy: Victimae paschali laudes (Praise the Paschal Victim), Veni Sancte Spiritus (Come Holy Spirit), Lauda Sion (Praise Zion), and Dies irae (Day of Wrath). The Stabat Mater (At the Cross the Mother Standing) was reinstated in 1727.