Trio sonata

The trio sonata is a musical form that was popular from the last decades of the 17th century to the first half of the 18th century.

A trio sonata is written for two or three solo melodic instruments and basso continuo, making three parts in all, hence the name trio sonata. However, because the basso continuo is usually made up of at least two instruments (typically a cello or bass viol and a keyboard instrument such as the harpsichord), performances of trio sonatas typically involve at least four musicians, and some 18th-century published editions have duplicate partbooks for the bass (Mangsen 2001).

The trio sonatas by Arcangelo Corelli (Opus 1, 1681, Opus 2, 1685, Opus 3, 1689, and Opus 4, 1694) were of unparalleled influence during his lifetime and for a long time after. The Opp. 1, 3, and 4 sonatas are of the sonata da chiesa type, whereas Op. 2 consists of sonate da camera (Talbot 2001b). Corelli's trios would serve as models for other composers well into the next century (Mattheson 1739, 345: §8).

The melody instruments used are often both violins. A well-known exception is the trio sonata in Johann Sebastian Bach's The Musical Offering, which is for violin and flute. Other trio sonatas by Bach include:

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