The principle of variation: theme, chaconne and passacaglia

What is variation in music?

Variation is the principle by which, after a phrase or theme is heard, the composer reprises it with transformations while keeping the original phrase structure (often 4, 8 or 16 bars). Common from the Baroque through the twentieth century, it appears as an independent genre (theme and variations), as a movement plan (sonata, quartet, symphony), or over an obstinate bass (chaconne, passacaglia). For the singer, it is the model of ornament and transformed reprise.

Chaconne and passacaglia: the theme in the bass

When the varied theme sits in the bass, one often speaks of chaconne or passacaglia, with a frame of 4, 8 or 16 bars. The passacaglia is both a dance movement on an obstinate bass and a rondo-like or variation composition similar to the chaconne, built on a theme (usually eight bars) repeated continuously. In the instrumental suite, the principle runs through certain slow triple-time dances: a harmonic foundation in the bass, over which variations unfold.

In J.S. Bach, the famous chaconne of the Solo Violin Partita no. 2 in D minor shows how dense writing can grow over a repeated bass cycle. Singers find a model for hearing the bass and progressively transforming the upper line, useful whenever a Baroque aria rests on ostinato or dance structure.

Variation as a movement structure

The variation principle also shapes a movement inside other genres: the sonata, the string quartet, the symphony. Examples: the second movement of Beethoven's Sonata no. 23 Appassionata; the second movement of Haydn's Symphony no. 94 (« Surprise »). The theme is stated then repeated with changes of texture, dynamics or accompaniment, without leaving the phrase-structure logic.

In the classical plan of a sonata or symphony, the slow movement may thus adopt theme and variations rather than lied form or sonata form. The singer reads a discourse: present clearly, transform without losing the thread, conclude with a last reprise often more ornate or calmer.

Timeline and key works

• Baroque: chaconne and passacaglia on ostinato bass; partita as variation series or suite; Bach (chaconne of Violin Partita no. 2).
• Classical: theme and variations (Mozart, Ah vous dirai-je, maman); slow movement in variations (Haydn, Symphony no. 94 « Surprise »).
• Beethoven: Diabelli Variations; 2nd movement of the Appassionata sonata.
• Romantic: Brahms, Variations on a Theme by Haydn.
• 20th c.: Jehan Alain, Variations on a Theme by Clément Janequin; the principle remains active in many languages.

Frequently asked questions about variation

What is the definition of variation in music?

Presentation of a motif or theme in a different form, generally keeping the original phrase structure; a form or principle present from the Baroque to the twentieth century.

What is the difference between chaconne and passacaglia?

Both often rest on an obstinate bass and a theme of 4 to 16 bars; the passacaglia is also a dance on ostinato bass and a form close to rondo or variations, similar to the chaconne.

What types of variation exist?

Melodic (ornamental), amplifying, harmonic, contrapuntal, instrumental or orchestral, and character variation; plus procedures such as note elimination.

Where does variation appear outside « theme and variations »?

In a movement of sonata, quartet or symphony, and in the slow dances of the suite (chaconne, passacaglia) over a harmonic bass foundation.

How does variation help the singer?

It trains the ear for ornament and transformed reprise: arias, da capo, cadenzas, while keeping structure and breath.