Close harmony
Close harmony is an arrangement of the notes of chords within a narrow range, usually notes that are no more than an octave apart. It is different from open harmony or voicing in that it uses each part on the closest harmonizing note (such as C4–E4–G4), while the open voicing uses a broader pitch array (like C3–G3–E4) expanding the harmonic range past the octave. Close harmony or voicing can refer to both instrumental and vocal arrangements. It can follow the standard voice-leading rules of classical harmony, as in string quartets or Bach's Chorales, or proceed in parallel motion with the melody in 3rds or 6ths.
Impressionist composers like Claude Debussy and Maurice Ravel often used close harmony in their works and other intervals, such as 7ths, 9ths, and 11ths may be used, since the chords have 4 or more notes and the harmonies are more complex. In jazz, this influence is reflected in George Gershwin's work.
Origins of this style of singing are found in harmonies of the 1800s in America. Early radio quartets continued this tradition. Female harmonists, like the Boswell Sisters (Mood Indigo,1933). The Hamilton Sisters and Fordyce (Who?You That's Who!, 1927), then became Three X Sisters. Both performed and recorded this style in the 1920s, and continued this onto commercial radio of the 1930s. Close harmony singing was especially popular in the 1940s with Pop and R&B groups using the technique quite frequently. The Andrews Sisters capitalized on a similar style too with Swing music. The Chordettes (Mr.Sandman, 1954), and the Supremes (Where Did Our Love Go?, 1964). Many gospel and soul groups in the 1950s and 60s also used this technique, usually 3- or 4-part SSAA or TTBB harmony with one person (either Bass or Lead) doing a call-and-response type lead. Examples of this are The Blind Boys of Alabama, a group that is still recording today. The folk-rock duo Simon & Garfunkel used close harmony, echoing their chosen role-models, The Everly Brothers.The Louvin Brothers were a duo that used close harmony in the genre of country music.
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