Exposition

What it means

The exposition is the first main part of a form, in which the thematic material is presented. The term is used in two forms whose layout differs: in the sonata movement and in the fugue. In both cases the exposition is the part in which the listener gets to know what is worked out in the further course.

Musical use

In the sonata movement the exposition in its usual shape consists of several sections. At the beginning stands the main theme in the home key. A transition modulates into a second key — in major pieces usually the dominant, in minor pieces usually the relative major. There the secondary theme sounds, which often forms a contrast to the main theme. A closing group or codetta confirms the new key. In classical practice the exposition is often repeated, which is indicated by repeat signs. The tension between the two keys is resolved only in the recapitulation, where the secondary theme also appears in the home key.

In the fugue the exposition is the section in which the subject is introduced in all the voices one after another. The first voice brings it in the home key, the second as the answer usually at the dominant level, the third again on the tonic level, and so on. While one voice takes over the subject, the preceding one leads a counter-voice, often a retained countersubject. Short codettas can mediate between the entries. The exposition ends when all the voices have entered.

In the fugue, the exposition designates the first pass in which each voice presents the subject once, alternating between the original form and the answer at the dominant. In the sonata movement it contains main theme, transition, secondary theme, and closing group and is often repeated in the Classical period. The exposition sets up the opposition between home key and secondary key that the recapitulation later resolves.

Performance practice

In a sonata exposition, make the change of key clear to yourself and shape the transition as movement toward it. In the fugue exposition, bring out each subject entry and take the other voices back while doing so. And, at repeat signs, decide deliberately whether and how you repeat.