Form
Binary and Ternary Form: Dance Patterns to Art Music
Simple and rounded binary, ABA and da capo: the cadence plans that define each section and how dances grew into art forms.
Binary form
A two-part form, AB or AABB, in which each part is usually repeated and the first part moves from the tonic toward the dominant.
Also called: Two-part form, AB form
Binary form is a two-part structure, written AB or, with repeats, AABB. The first section usually moves from the tonic to a closing cadence in the dominant or the relative major, and the second section travels back to the tonic. Many Baroque dance movements, such as sarabandes and gigues, use binary form with both sections repeated. In rounded binary, the second section ends by returning material from the first, which gives the form a sense of closure. The minuet proper is often in binary form, with each half repeated. Binary form is the basic form of many early keyboard pieces, and its clear division into two halves makes it easy to follow.
Related terms
- Ternary formA three-part ABA form in which a contrasting middle section is framed by a return of the opening material, usually in the tonic.
- RondoA form built on a main theme that returns between contrasting episodes, typically in the pattern ABACA or ABACABA.
- Sonata formThe form of many first movements: an exposition of two contrasting themes, a development, and a recapitulation that returns both themes in the tonic.
- PhraseA unit of melody or harmony, usually around four bars in tonal music, that ends with a cadence and forms a complete musical thought.