- Michael Tilmouth
- , revised by Basil Smallman
A composition for piano and two other instruments, usually violin and cello; standard variants include piano with flute and cello (Weber j259), clarinet and viola (Mozart k498, Schumann op.88), clarinet and cello (Beethoven op.11 and Brahms op.114), and violin and horn (Brahms op.40). The genre emerged in the mid-18th century from the Baroque duo and trio sonatas and the keyboard sonata through a shift of emphasis from the string parts to the keyboard (see Sonata, §2 and Sonata, §3; Accompanied keyboard music).
Obbligato writing (as opposed to continuo parts) for keyboard instruments occasionally appeared in late Baroque chamber music. In a number of J.S. Bach’s sonatas, for example (including those for violin, flute or viola da gamba and harpsichord), the texture is predominantly one of three equally important parts, two of them carried by the harpsichord. In his sonatas for harpsichord and violin op.3 (1734...