String quartet Violini, Violetta [viola], e Violoncello senza Cembalo" (Sonata for four instruments: two violins, viola, and cello without harpsichord), this was a natural evolution from the existing tradition. The string quartet in its now accepted form came about with Haydn. If the combination of two violins, viola and cello was not unknown before Haydn, when it occurred in chamber music it was more likely through circumstance than conscious design; certainly the string quartet enjoyed no recognized status as an ensemble in the way that two violins with basso continuo – the so-called 'trio sonata' – had for more than a hundred
String quartet is often in Rondo form or Sonata rondo form, in the tonic key. Some quartets play together for many years in ensembles which may be named after the first violinist (e.g. the Takács Quartet), a composer (e.g. the Borodin Quartet) or a location (e.g. the Budapest Quartet). Well-known string quartets can be found in the list of string quartet ensembles. The early history of the string quartet is in many ways the history of Haydn's journey with the genre. Not that he composed the first quartet of all: before Haydn alighted on the genre there had been several spasmodic examples