A quintet is a group containing five members. It is commonly associated with musical groups, such as a string quintet, or a group of five singers, but can be applied to any situation where five similar or related objects are considered a single unit. 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. A piece of music written for such a group is similarly named.
In jazz music, a quintet is group of five players, usually consisting of two of any of the following instruments, guitar, trumpet, saxophone, clarinet, flute or trombone in addition to traditional jazz trio – piano, double bass, drums.
In some modern bands there are quintets formed from the same family of instruments with various voices, as an all-brass ensemble, or all saxophones, in soprano, alto, baritone, and bass, and sometimes double bass. The standard woodwind quintet, for example, consists of one player each on flute, oboe, clarinet, bassoon, and French horn, while the standard brass quintet has two trumpets, French horn, trombone, and tuba or bass trombone. Any combination, however, is possible.
Many rock, pop, and metal bands are made up of five people, normally consisting of two guitarists, a bassist, a drummer, and a lead vocalist. This is normally considered to the maximum size of most bands. However, several bands like Linkin Park, Slipknot, Guns N' Roses, and DragonForce have more than 5 band members. Having more than five members is mostly uncommon in rock and pop music.
It is becoming increasingly common in a cappella and barbershop music circles to use the fifth voice as vocal percussionist, with the remainder being a traditional SATB (soprano alto tenor bass) quartet, or perhaps SSAA or TTBB.