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Augmented seventh chord

From Wikipedia, the free encyclopedia

augmented seventh chord
Component intervals from root
minor seventh
augmented fifth
major third
root
Tuning
80:100:125:144
Forte no. / Complement
4-24 / 8-24
Augmented dominant seventh chord on C

The augmented seventh chord, or seventh augmented fifth chord,[1] or seventh sharp five chord is a seventh chord composed of a root, major third, augmented fifth, and minor seventh (1, 3, 5, 7).[2] It can be viewed as an augmented triad with a minor seventh.[3] When using popular-music symbols, it is denoted by +7, aug7,[2] or 75. For example, the augmented seventh chord built on A, written as A+7, has pitches A-C-E-G:


{
\override Score.TimeSignature #'stencil = ##f
\relative c' {
   \clef treble 
   \time 4/4
   \key c \major
   <as c e ges>1
} }

The chord can be represented by the integer notation {0, 4, 8, 10}.

Use

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The root is the only optional note in an augmented seventh chord, the fifth being required because it is raised.[4] This alteration is useful in the major mode because the raised 5th creates a leading tone to the 3rd of the tonic triad.[3] See also dominant.

In rock parlance, the term augmented seventh chord is sometimes confusingly and erroneously used to refer to the so-called "Hendrix chord", a 79 chord which contains the interval of an augmented ninth but not an augmented fifth.[5]


{
\override Score.TimeSignature #'stencil = ##f
\relative c' { 
  \clef treble 
  \time 6/4 c4^\markup { "C whole tone scale" } d e fis gis ais \time 4/4 c1 \bar "||"
  \time 4/4 <c, e gis bes>1 \bar "||"
} }
One chord-scale option for an augmented dominant seventh chord (+7th) is the whole tone scale.[6]

The augmented minor seventh chord may be considered an altered dominant seventh and may use the whole tone scale, as may the dominant seventh flat five chord.[7] See chord-scale system.

The augmented seventh chord normally acts as a dominant, resolving to the chord a fifth below.[8] Thus, G aug7 resolves to a C major or minor chord, for example.


{
\override Score.TimeSignature #'stencil = ##f
\relative c' {
   \clef treble 
   \time 4/4
   \key c \major
   <b dis f g>1 <c e e g> \bar "||"
} }

Overall, however, the augmented seventh chord is infrequently used, often with the raised fifth degree being the result of a chromatic passing tone.[9]

Augmented seventh chord table

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Chord Root Major third Augmented fifth Minor seventh
Caug7 C E G B
Caug7 C E (F) Gdouble sharp (A) B
Daug7 D F A C (B)
Daug7 D F A C
Daug7 D Fdouble sharp (G) Adouble sharp (B) C
Eaug7 E G B D
Eaug7 E G B (C) D
Faug7 F A C E
Faug7 F A Cdouble sharp (D) E
Gaug7 G B D F (E)
Gaug7 G B D F
Gaug7 G B (C) Ddouble sharp (E) F
Aaug7 A C E G
Aaug7 A C E (F) G
Aaug7 A Cdouble sharp (D) Edouble sharp (F) G
Baug7 B D F A
Baug7 B D Fdouble sharp (G) A

See also

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References

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  1. ^ Kroepel, Bob (1993). Mel Bay Creative Keyboard's Deluxe Encyclopedia of Piano Chords: A Complete Study of Chords and How to Use Them, p. 15. ISBN 0-87166-579-4.
  2. ^ a b Garner, Robert (2007). Mel Bay Presents Essential Music Theory for Electric Bass, p. 69. ISBN 0-7866-7736-8.
  3. ^ a b Kostka, Stefan; Payne, Dorothy (2004). "The Dominant with a Raised 5th". Tonal Harmony with an Introduction to Twentieth-Century Music (6th ed.). New York. pp. 446–447. ISBN 978-0-07-332713-6.{{cite book}}: CS1 maint: location missing publisher (link)
  4. ^ Latarski, Don (1991). An Introduction to Chord Theory, p. 29. ISBN 0-7692-0955-6.
  5. ^ Radio: "Shiver down the backbone – Jimi Hendrix comes to Radio 3", The Spectator, by Kate Chisholm, Wednesday, 21 November 2007
  6. ^ Hatfield, Ken (2005). Jazz and the Classical Guitar Theory and Applications, p. 121. ISBN 0-7866-7236-6.
  7. ^ Berle, Annie (1996). Contemporary Theory and Harmony, p. 100. ISBN 0-8256-1499-6.
  8. ^ Bay, William (1994). Mel Bay Complete Jazz Sax Book, p. 64. ISBN 0-7866-0229-5.
  9. ^ Ottman 1992, p. 282.

Bibliography

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