1. It has four parts - no more, no less.
2. It has melodies that are easily remembered.
3. Barbershop harmonic structure is characterized by:
   • a strong bass line
   • melody in an internal part
   • complete chords without any non-chord tones
   • mostly major triads, dominant 7th chords and dominant 9th chords with other chords used in passing as demanded by the implied harmony
   • traditional harmonic movement and resolutions
4. It has rhythmic interest as an important and vital part of an uptune.
5. It has clear, recognizable form.
6. It has lyrics that are clear and understandable.
7. It is challenging to perform because:
   • it requires great vocal skill and is usually sung by amateur singers
   • all chords must be heard with clarity requiring singers to sing precise intervals
8. Properly tuned barbershop chords are congruent with the physics of sound.
9. Energy and physical involvement are required from the singer in a degree of intensity not usually found in other choral forms.
10. The artistic potential is unlimited since we are not bound by the printed page.
11. It is emotionally satisfying to both the listener and the performer.
12. You can't do it alone.
    
    

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Lock and Ring: The ultimate barbershop sound. To achieve it requires excellence in all phases of singing -- a good musical arrangement, good vocal technique, well balanced and blended voices and accuracy of intonation. In combination, these qualities can create an audible overtone that sends a chill up the spine of singers and listeners alike.

Mass Sing:A Sweet Adelines tradition. This is a public event integrated into the business of a convention. Everyone in attendance is invited to gather in a public place and present listeners with a sample of barbershop harmony. It is often used as a way to thank the city hosting the gathering.

Pitch Pipe: A chromatic scaled instrument which is blown to establish a pitch or key tone. The one most generally used by a cappella singers is small and round, containing 13 pitches.

A cappella: Choral music without instrumental accompaniment. Cappella (Italian) chapel; a cappella in the manner of the chapel.

Woodshedding: An impromptu gathering of singers who improvise the harmony of a song by ear. This is the very heart of barbershop singing and is the essence of barbershop's heritage.

Tag:  The final portion of a barbershop arrangement, usually containing very interesting chord progressions that are fun to sing. Tags may be sung separately from the song and are often used both by quartets and choruses for the purpose of practicing to achieve complete chord excellence.