Barbershop music in tags or codas, or when some appropriate embellishment can be created. One characteristic feature of barbershop harmony is the use of what is known as "snakes" and "swipes." This is when a chord is altered by a change in one or more non-melodic voices. Occasional passages may be sung by fewer than four voice parts. Barbershop music is generally performed by either a barbershop quartet, a group of four singers with one on each vocal part, or a barbershop chorus, which closely resembles a choir with the notable exception of the genre of music. According to the Barbershop Harmony
Barbershop arranging Barbershop arranging Barbershop arranging is the art of creating arrangements of barbershop music. The Barbershop Harmony Society (BHS) and Sweet Adelines International (SAI) have prescribed rules that dictate what is an acceptable arrangement, particularly with regard to singing in competition. This makes barbershop arranging a specialist form of arranging, rarely tackled by those outside Barbershop; likewise, barbershop arrangers tend to be known only for their barbershop arrangements rather than for their work in any other musical form. The following 2 paragraphs from the BHS indicate technical requirements of a barbershop arrangement for use in a BHS contest: “Barbershop harmony is