Popular vocal ensemble consisting of four unaccompanied male voices.
The voice parts are tenor, lead, baritone, and bass, with the lead normally singing the melody and the tenor harmonizing above. The emphasis is on close harmony, synchronization of word sounds, and variation of tempo, volume, diction, and phrasing. Barbershop apparently originated in the U.S. in the late 19th century, when American barbershops formed social and musical centres for neighbourhood men, though the term may derive from "barber's music," the British term for an extemporized performance by patrons waiting to be shaved and referring to a barber's traditional role as a musician.