Ostinato
In music, an ostinato is a motif or phrase that persistently repeats in the same musical voice, frequently in the same pitch.
Both ostinatos and ostinati are accepted English plural forms, the latter reflecting the word's Italian etymology.
Well-known ostinato-based pieces include classical compositions such as Ravel's Boléro and the Carol of the Bells, and popular songs such as John Lennon's "Mind Games", Donna Summer and Giorgio Moroder's "I Feel Love", Henry Mancini's theme from Peter Gunn, The Who's "Baba O'Riley", The Verve's "Bitter Sweet Symphony", and Flo Rida's "Low".
The repeating idea may be a rhythmic pattern, part of a tune, or a complete melody in itself. Strictly speaking, ostinati should have exact repetition, but in common usage, the term covers repetition with variation and development, such as the alteration of an ostinato line to fit changing harmonies or keys.
Within the context of European classical and film music, Claudia Gorbman defines an ostinato as a repeated melodic or rhythmic figure that propels scenes that lack dynamic visual action.
Ostinati play an important part in improvised music, in which they are often referred to as riffs or vamps. A "favorite technique of contemporary jazz writers", ostinati are often used in modal and Latin jazz and traditional African music including Gnawa music.
The term ostinato essentially has the same meaning as the medieval Latin word pes, the word ground as applied to classical music, and the word riff in contemporary popular music.
European classical music
Within the domain of European classical music traditions, Ostinati are used in 20th-century music to stabilize groups of pitches, as in Stravinsky's The Rite of Spring ''Introduction and Augurs of Spring. A famous type of ostinato, called the Rossini crescendo'', owes its name to a crescendo that underlies a persistent musical pattern, which usually culminates in a solo vocal cadenza. This style was emulated by other bel canto composers, especially Vincenzo Bellini; and later by Wagner.Applicable in homophonic and contrapuntal textures, they are "repetitive rhythmic-harmonic schemes", more familiar as accompanimental melodies, or purely rhythmic. The technique's appeal to composers from Debussy to avant-garde composers until at least the 1970s "... lies in part in the need for unity created by the virtual abandonment of functional chord progressions to shape phrases and define tonality". Similarly, in modal music, "... relentless, repetitive character help to establish and confirm the modal center". Their popularity may also be justified by their ease as well as range of use, though, "... ostinato must be employed judiciously, as its overuse can quickly lead to monotony".
Medieval
Ostinato patterns have been present in European music from the Middle Ages onwards. In the famous English canon "Sumer Is Icumen In", the main vocal lines are underpinned by an ostinato pattern, known as a pes:File:Sumer is Icumen in.png|thumb|center|500px|Later in the medieval era, Guillaume Dufay's 15th-century chanson Resvelons Nous features a similarly constructed ostinato pattern, but this time 5 bars long. Over this, the main melodic line moves freely, varying the phrase-lengths, while being "to some extent predetermined by the repeating pattern of the canon in the lower two voices." File:Dufay Resvelons nous 02.png|thumb|center|500px|
Ground bass: Late Renaissance and Baroque
Ground bass or basso ostinato is a type of variation form in which a bass line, or harmonic pattern is repeated as the basis of a piece underneath variations. Aaron Copland describes basso ostinato as "... the easiest to recognize" of the variation forms wherein, "... a long phrase—either an accompanimental figure or an actual melody—is repeated over and over again in the bass part, while the upper parts proceed normally ". However, he cautions, "it might more properly be termed a musical device than a musical form."One striking ostinato instrumental piece of the late Renaissance period is "The Bells", a piece for virginals by William Byrd. Here the ostinato consists of just two notes:
In Italy, during the seventeenth century, Claudio Monteverdi composed many pieces using ostinato patterns in his operas and sacred works. One of these was his 1650 version of "Laetatus sum", an imposing setting of Psalm 122 that pits a four-note "ostinato of unquenchable energy." against both voices and instruments:File:Monteverdi Laetatus sum Ground bass.png|thumb|center|500px|Monteverdi Laetatus sum
Later in the same century, Henry Purcell became famous for his skilful deployment of ground bass patterns. His most famous ostinato is the descending chromatic ground bass that underpins the aria "When I am laid in earth" at the end of his opera Dido and Aeneas: While the use of a descending chromatic scale to express pathos was fairly common at the end of the seventeenth century, Richard Taruskin pointed out that Purcell shows a fresh approach to this musical trope: "Altogether unconventional and characteristic, however, is the interpolation of an additional cadential measure into the stereotyped ground, increasing its length from a routine four to a haunting five bars, against which the vocal line, with its despondent refrain, is deployed with marked asymmetry. That, in addition to Purcell's distinctively dissonant, suspension-saturated harmony, enhanced by additional chromatic descents during the final ritornello and by many deceptive cadences, makes this little aria an unforgettably poignant embodiment of ." See also: Lament bass.
However, this is not the only ostinato pattern that Purcell uses in the opera. Dido's opening aria "Ah, Belinda" is a further demonstration of Purcell's technical mastery: the phrases of the vocal line do not always coincide with the four-bar ground:File:Dido's opening aria "Ah! Belinda".png|thumb|center|500px|Dido's opening aria
"Purcell's compositions over a ground vary in their working out, and the repetition never becomes a restriction." Purcell's instrumental music also featured ground patterns. A particularly fine and complex example is his Fantasia upon a Ground for three violins and continuo: File:Purcell Fantasia in 3 parts to a ground.png|thumb|center|500px|Purcell Fantasia in 3 parts to a
The intervals in the above pattern are found in many works of the Baroque Period. Pachelbel's Canon also uses a similar sequence of notes in the bass part:
Two pieces by J.S.Bach are particularly striking for their use of an ostinato bass: the Crucifixus from his Mass in B minor and the Passacaglia in C minor for organ, which has a ground rich in melodic intervals: The first variation that Bach builds over this ostinato consists of a gently syncopated motif in the upper voices: This characteristic rhythmic pattern continues in the second variation, but with some engaging harmonic subtleties, especially in the second bar, where an unexpected chord creates a passing implication of a related key: In common with other Passacaglias of the era, the ostinato is not simply confined to the bass, but rises to the uppermost part later in the piece: A performance of the entire piece can be heard .
Late eighteenth and nineteenth centuries
Ostinatos feature in many works of the late 18th and early 19th centuries. Mozart uses an ostinato phrase throughout the big scene that ends Act 2 of the Marriage of Figaro, to convey a sense of suspense as the jealous Count Almaviva tries in vain to incriminate the Countess, his wife, and Figaro, his butler, for plotting behind his back. A famous type of ostinato, called the Rossini crescendo, owes its name to a crescendo that underlies a persistent musical pattern, which usually culminates in a solo vocal cadenza.In the energetic Scherzo of Beethoven’s late C sharp minor Quartet, Op. 131, there is a harmonically static passage, with "the repetitiveness of a nursery rhyme" that consists of an ostinato shared between viola and cello supporting a melody in octaves in the first and second violins: Beethoven reverses this relationship a few bars later with the melody in the viola and cello and the ostinato shared between the violins:
Both the first and third acts of Wagner's final opera Parsifal feature a passage accompanying a scene where a band of Knights solemnly processes from the depths of forest to the hall of the Grail. The "Transformation music" that supports this change of scene is dominated by the iterated tolling of four bells:File:Wagner, Parsifal Act 1, transformation music.png|thumb|center|500px|Wagner, Parsifal Act 1, Brahms used ostinato patterns in both the finale of his Fourth Symphony and in the closing section of his Variations on a Theme by Haydn: File:Brahms Variations on a Theme by Haydn, final section with ground bass.png|thumb|center|500px|Brahms Variations on a Theme by Haydn, final section with
Twentieth century
featured an ostinato pattern throughout his Piano Prelude "Des pas sur la neige". Here, the ostinato pattern stays in the middle register of the piano – it is never used as a bass. "Remark that the footfall ostinato remains nearly throughout on the same notes, at the same pitch level... this piece is an appeal to the basic loneliness of all human beings, oft-forgotten perhaps, but, like the ostinato, forming a basic undercurrent of our history." File:Debussy, Des pas sur la neige.png|thumb|center|500px|Debussy, Of all the major classical composers of the 20th century, Stravinsky is possibly the one most associated with the practice of ostinato. In conversation with the composer, his friend and colleague Robert Craft remarked "Your music always has an element of repetition, of ostinato. What is the function of ostinato?" Stravinsky replied; "It is static – that is, anti-development; and sometimes we need a contradiction to development." Stravinsky was particularly skilled at using ostinatos to confound rather than confirm rhythmic expectations. In the first of his Three Pieces for String Quartet, Stravinsky sets up three repeated patterns, which overlap one another and never . "Here a rigid pattern of bars is laid over a strictly recurring 23-beat tune, so that their changing relationship is governed primarily by the pre-compositional scheme." "The rhythmical current running through the music is what binds together these curious mosaic-like pieces."A subtler metrical conflict can be found in the final section of Stravinsky's Symphony of Psalms. The choir sing a melody in triple time, while the bass instruments in the orchestra play a 4-beat ostinato against this. "This is built up over an ostinato bass moving in fourths like a ."