String trio String trio A string trio is a group of three string instruments or a piece written for such a group. The term is generally used with reference to works of chamber music from the Classical period to the present. From at least the 19th century on, the term "string trio" with otherwise unspecified instrumentation normally refers to the combination violin, viola and cello (cf "string quartet", "piano trio" etc.). This is how the term is used by major catalogs, including IMSLP. The earliest string-trio form, found in the early Classical period, consisted of two violins and a cello, a grouping
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