Quartett

: a group or set of four people or things.

a group of four instruments with strings that play together: A string quartet consists of two violins, a viola, and a cello. nspimages/iStock/Getty Image Plus/GettyImages.

an organized group of four singers or players.

A quartet is a group of four people who play musical instruments or sing together.

noun. a musical composition scored for piano and three other instruments, typically violin, viola, and cello. an instrumental group consisting of a pianist and three other musicians, typically a violinist, violist, and cellist.

String quartets most often consist of two violins, a viola, and a cello. The particular choice and number of instruments derives from the registers of the human voice: soprano, alto, tenor and bass (SATB).

The string quartet can be defined in several ways. At the most basic level the musical term refers to the medium of four string instruments: two violins, viola, and violoncello. It can also be used to describe the collective identity of the instrumentalists themselves, in particular established professional ensembles.

The four voices are: the lead, the vocal part which typically carries the melody; a bass, the part which provides the bass line to the melody; a tenor, the part which harmonizes above the lead; and a baritone, the part that frequently completes the chord.

Another prominent instrumental genre that originates in the Classical era is the string quartet. String quartets were the most popular genre of chamber music in the Classical era and are always written for the same four instruments: two violins, one viola, and one cello.

Overview. In classical instrumental music, any additional instrument (such as a piano, clarinet, oboe, etc.) joined to the usual string quartet (two violins, a viola, and a cello), gives the resulting ensemble its name, such as "piano quintet", "clarinet quintet", etc.

Both genres are constructed in similar ways, but the difference between them lies in how large the ensemble is. The Symphony is a 4-movement work (also called a 4-movement cycle) for an orchestra, while a String Quartet is a 4-movement work for a string quartet.

An Oboe quartet is a composition scored for oboe, violin, viola and basso. While the genre is not very common, Mozart wrote the most well known, his Oboe Quartet, K. 370.