Chamber music is a form of classical music, written for a small group of instruments which traditionally could be accommodated in a palace chamber. Most broadly, it includes any art music that is performed by a small number of performers with one performer to a part. The word "chamber" signifies that the music can be performed in a small room, often in a private salon with an intimate atmosphere. However, it usually does not include, by definition, solo instrument performances.

Because of its intimate nature, chamber music has been described as "the music of friends." For more than 200 years, chamber music was played primarily by amateur musicians in their homes, and even today, when most chamber music performance has migrated from the home to the concert hall, there are still many musicians, amateur and professional, who continue to play chamber music for their own pleasure. Playing chamber music requires special skills, both musical and social, which are different from the skills required for playing solo or symphonic works.

Goethe described chamber music (specifically, string quartet music) as "four rational people conversing." This conversational paradigm has been a thread woven through the history of chamber music composition from the end of the 18th century to the present. The analogy to conversation recurs in descriptions and analyses of chamber music compositions.

History of chamber music

From its earliest beginnings in the Baroque period to the present, chamber music has been a reflection of the changes in the technology and the society that produced it.

Early beginnings

During the Baroque period, chamber music as a genre was not clearly defined. Often, works could be played on any variety of instruments, in orchestral or chamber ensembles. The Art of the Fugue by Johann Sebastian Bach, for example, can be played on a keyboard instrument (harpsichord or organ) or by a string quartet or string orchestra. The instrumentation of trio sonatas was also often not clearly specified; Handel's trio sonatas opera 1 - 5, for example, were written for "violins or flutes or oboes". Bass lines could be played by violone, cello, theorbo, or bassoon, and sometimes three or four instruments would join in the bass line in unison. Sometimes composers mixed movements for chamber ensembles with orchestral movements. Telemann's 'Tafelmusik' (1733), for example, has five sets of movements for various combinations of instruments, ending with a full orchestral section.

Baroque chamber music was primarily contrapuntal. That is, each instrument played the same melodic material in sequence, creating a complex, interwoven fabric of sound. Because each instrument was playing essentially the same melodic line, all the instruments were equal. In the trio sonata, there is no ascendent or solo instrument, but all three instruments share equal importance.