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Major seventh

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(Redirected from Semidiminished octave)
major seventh
Inverseminor second
Name
Other namessupermajor seventh
AbbreviationM7
Size
Semitones11
Interval class1
Just interval15:8,[1] 50:27
Cents
12-Tone equal temperament1100
Just intonation1088, 1067
Major seventh Play

In music from Western culture, a seventh is a musical interval encompassing seven staff positions (see Interval number for more details), and the major seventh is one of two commonly occurring sevenths. It is qualified as major because it is the larger of the two. The major seventh spans eleven semitones, its smaller counterpart being the minor seventh, spanning ten semitones. For example, the interval from C to B is a major seventh, as the note B lies eleven semitones above C, and there are seven staff positions from C to B. Diminished and augmented sevenths span the same number of staff positions, but consist of a different number of semitones (nine and twelve).

The intervals from the tonic (keynote) in an upward direction to the second, to the third, to the sixth, and to the seventh scale degrees (of a major scale are called major.[2]

The easiest way to locate and identify the major seventh is from the octave rather than the unison, and it is suggested that one sings the octave first.[3] For example, the most commonly cited example of a melody featuring a major seventh is the tonic-octave-major seventh of the opening to "(Somewhere) Over the Rainbow".[3] "Not many songwriters begin a melody with a major seventh interval; perhaps that's why there are few memorable examples."[4] However, two songs provide exceptions to this generalisation: Cole Porter's "I love you" (1944) opens with a descending major seventh and Jesse Harris's "Don't Know Why",(made famous by Norah Jones in her 2002 debut album, Come Away with Me), starts with an ascending one. In the refrain of "Bali Hai" in "South Pacific," the third tone ("Hai") is a major seventh to the first ("Ba-").

The major seventh occurs most commonly built on the root of major triads, resulting in the chord type also known as major seventh chord or major-major seventh chord: including I7 and IV7 in major.[5] "Major seven chords add jazziness to a musical passage. Alone, a major seventh interval can sound ugly."[6]

A major seventh in just intonation most often corresponds to a pitch ratio of 15:8 (play); in 12-tone equal temperament, a major seventh is equal to eleven semitones, or 1100 cents, about 12 cents wider than the 15:8 major seventh. In 24-tone equal temperament a supermajor seventh, semiaugmented seventh or, semidiminished octave, 23 quarter-tones, is 1150 cents (Play). The small major seventh is a ratio of 9:5,[7] now identified as a just minor seventh. 35:18, or 1151.23 cents, is the ratio of the septimal semi-diminished octave.[8] The 15:8 just major seventh occurs arises in the extended C major scale between C & B and F & E.[9] Play F & E

The major seventh interval is considered one of the most dissonant intervals after its inversion the minor second. For this reason, its melodic use is infrequent in classical music. However, in the genial Gavotte from J.S. Bach’s Partita in E major for solo violin, a major seventh features both as a chord (bar 1) and as a melodic interval (bar 5):

Bach Gavotte from Partita 3 for Violin
Bach Gavotte from Partita 3 for Violin.

Another piece that makes more dramatic use of the major seventh is "The Hut on Fowl's Legs" from Mussorgsky's piano suite Pictures at an Exhibition (1874).

Mussorgsky, 'The Hut on Fowl's Legs', piano version
Mussorgsky 'The Hut on Fowl's Legs', piano version.

Another is the closing duet from Verdi's Aida, "O terra addio".[10] During the early 20th century, the major seventh was used increasingly both as a melodic and a harmonic interval, particularly by composers of the Second Viennese School. Anton Webern's Variations for Piano, Op. 27, opens with a major seventh and the interval recurs frequently throughout the piece.

Pythagorean major seventh (243:128) on C Play, five Pythagorean perfect fifths.

Under equal temperament this interval is enharmonically equivalent to a diminished octave (which has a similar musical use to the augmented unison).

The major seventh chord is however very common in jazz, especially 'cool' jazz, and has a characteristically soft and sweet sound: think of the first chord in "The Girl from Ipanema".[citation needed] The major seventh chord consists of the first, third, fifth and seventh degrees (notes) of the major scale. In the key of C, it comprises the notes C E G and B.

See also

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References

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  1. ^ Haluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxiii. ISBN 0-8247-4714-3. Classic major seventh.
  2. ^ Benward, Bruce & Saker, Marilyn (2003). Music: In Theory and Practice, Vol. I, p.52. Seventh Edition. ISBN 978-0-07-294262-0.
  3. ^ a b Keith Wyatt, Carl Schroeder, Joe Elliott (2005). Ear Training for the Contemporary Musician, p.69. ISBN 0-7935-8193-1.
  4. ^ Neely, Blake (2009). Piano For Dummies, p.201. ISBN 0-470-49644-4.
  5. ^ Benward & Saker (2003). Music: In Theory and Practice, Vol. I, p.229. Seventh Edition. ISBN 978-0-07-294262-0.
  6. ^ Starr, Eric (2007). The Everything Rock & Blues Piano Book: Master Riffs, Licks, and Blues Styles from New Orleans to New York City, p.84. ISBN 1-59869-260-7.
  7. ^ Royal Society (Great Britain) (1880, digitized Feb 26, 2008). Proceedings of the Royal Society of London, Volume 30, p.531. Harvard University.
  8. ^ Haluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxv. ISBN 0-8247-4714-3.
  9. ^ Paul, Oscar (1885). A manual of harmony for use in music-schools and seminaries and for self-instruction, p.165. Theodore Baker, trans. G. Schirmer.
  10. ^ Fleming, William and Veinus, Abraham (1958). Understanding Music, p.67. Holt. "Verdi's startling use of the rising major seventh in "O terra addio," the final duet of Aida,...creates an almost unbearable tension that perfectly expresses the infinite longing of the doomed lovers on the brink of eternity."