“Barbershop harmony is a style of unaccompanied vocal music characterized by consonant four-part chords for every melody note in a predominantly homophonic texture. Each of the four parts has its own role: the lead sings the melody, with the tenor harmonizing above the melody, the bass singing the lowest harmonizing notes, and the baritone completing the chord. The melody is not sung by the tenor or bass, except for an infrequent note or two to avoid awkward voice leading, in tags or codas, or when some appropriate embellishing effect can be created. Occasional brief passages may be sung by fewer than four voice parts.