Barbershop harmony is a style of unaccompanied vocal music characterized by consonant four-part chords for every melody note in a predominantly homophonic texture. The melody is consistently sung by the lead, 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 except for an infrequent note or two to avoid awkward voice leading, in tags and codas, or when some appropriate embellishing effect can be created. Occasional brief passages may be sung by fewer than four voice parts.
Barbershop music features songs with understandable lyrics and easily singable melodies whose tones clearly define a tonal center and imply major and minor chords and Barbershop (dominant and secondary dominant) seventh chords that resolve primarily around the circle of fifths while making frequent use of other resolutions. Barbershop music also features a balanced and symmetrical form and a standard meter.
The basic song and its harmonization are embellished by the arranger to provide support of the song's theme and to close the song effectively. Barbershop singers adjust pitches to achieve perfectly tuned chords in just intonation while remaining true to the established tonal center.
Artistic singing in the Barbershop style exhibits a fullness or expansion of sound, precise intonation, a high degree of vocal skill and a high level of unity and consistency within the ensemble. Ideally, these elements are natural, unmanufactured and free from apparent effort.
The presentation of Barbershop music uses appropriate musical and visual methods to convey the theme of the song and provide the audience with an emotionally satisfying and entertaining experience. The musical and visual delivery is from the heart, believable and sensitive to the song and its arrangement throughout. The most stylistic presentation artistically melds together the musical and visual aspects to create and sustain the illusions suggested by the music.
The Barbershop Harmony Society legally and historically named the Society for the Preservation and Encouragement of Barber Shop Quartet Singing in America, Inc. (SPEBSQSA), is the first of several organizations to promote and preserve barbershop music as an art form. Founded by Owen C. Cash in 1938, the organization quickly grew, promoting barbershop harmony among men of all ages. As of 2012, just under 25,000 men in the United States and Canada are members of this organization whose focus is on a cappella music. The international headquarters was in Kenosha, Wisconsin for fifty years before moving to Nashville, Tennessee in 2007.