Variations (music)

In music, variation is a formal technique where material is repeated in an altered form. The changes may involve melody, rhythm, harmony, counterpoint, timbre, orchestration or any combination of these.

Mozart’s Twelve Variations on "Ah vous dirai-je, Maman"(1785), known in the English-speaking world as “Twinkle, twinkle, little star” exemplifies a number of common variation techniques. Here are the first eight bars of the theme:

Mozart first variation decorates and elaborates the plain melodic line:

The fifth Variation breaks up the steady pulse and creates syncopated off-beats:

The seventh variation introduces powerful new chords, which replace the simple harmonies originally implied by the theme with a prolongational series of descending fifths:

In the elaborate 8th Variation, Mozart changes from the major to the parallel minor mode, while combining three techniques: counterpoint, suspensions and imitation:

A complete performance can be heard by following this link: Listen.

Variation techniques are frequently used within pieces that are not themselves in the form of Theme and Variations. For example, when the opening two-bar phrase of Chopin’s Nocturne in F minor returns later in the piece, it is instantly repeated as an elegant melodic re-working:

Debussy’s piano piece “Reflets dans l’Eau” (1905) opens with a sequence of chords:

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