Piano quartet

Piano quartet: A piano quartet is a small ensemble whose instrumentation is piano and three other instruments, usually violin, viola, and cello according to New Grove Online. The trend grew out of the accompanied piano concertos and divertimentos of the 1750s to 80s that were scored for piano, two violins, and cello.
The scoring and instrumentation has gone through a great deal of change as piano quartets started to become more popular. After about 1780 a shift towards violin, viola, and cello as the popular instrumentation for piano quartets. After about 1800, wind instruments also started to become a more popular in the piano quartet setting.
During the 1780s and 90s, the quartet scene grew immensely. Mozart was the most known at this time, but Haydn and Beethoven were also well known composers. Also during this time, the all of the instruments started to play an equal role in the quartet. For example, Mendelssohn and Brahms both deemphasized the piano in their quartets.
Composers have written for more varied groups in the 20th century. Anton Webern wrote a quartet for piano, violin, clarinet, and tenor sax and Olivier Messiaen wrote for piano, violin, cello and clarinet.