The augmented seventh chord, or seventh augmented fifth chord,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. . or seventh sharp five chord is a seventh chord composed of a root, major third, augmented fifth, and minor seventh (1, 3, 5, 7).Garner, Robert (2007). Mel Bay Presents Essential Music Theory for Electric Bass, p. 69. . It can be viewed as an augmented triad with a minor seventh. When using popular-music symbols, it is denoted by +7, aug7, or 75. For example, the augmented seventh chord built on A, written as A+7, has pitches A–C–E–G:
The chord can be represented by the integer notation {0, 4, 8, 10}.
Use The root is the only optional note in an augmented seventh chord, the fifth being required because it is raised.Latarski, Don (1991). An Introduction to Chord Theory, p. 29. . This alteration is useful in the major mode because the raised 5th creates a leading tone to the 3rd of the tonic triad. 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.Radio: "Shiver down the backbone – Jimi Hendrix comes to Radio 3", The Spectator, by Kate Chisholm, Wednesday, 21 November 2007 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.Berle, Annie (1996). Contemporary Theory and Harmony, p. 100. . See chord-scale system.
The augmented seventh chord normally acts as a dominant, resolving to the chord a fifth below.Bay, William (1994). Mel Bay Complete Jazz Sax Book, p. 64. . Thus, G aug7 resolves to a C major or minor chord, for example.
Overall, however, the augmented seventh chord is infrequently used, with the raised fifth degree often being the result of a chromatic passing tone.
Augmented seventh chord table {| class="wikitable" !Chord !Root !Major third !Augmented fifth !Minor seventh |- !Caug7 |C |E |G |B |- !Caug7 |C |E (F) |G (A) |B |- !Daug7 |D |F |A |C (B) |- !Daug7 |D |F |A |C |- !Daug7 |D |F (G) |A (B) |C |- !Eaug7 |E |G |B |D |- !Eaug7 |E |G |B (C) |D |- !Faug7 |F |A |C |E |- !Faug7 |F |A |C (D) |E |- !Gaug7 |G |B |D |F (E) |- !Gaug7 |G |B |D |F |- !Gaug7 |G |B (C) |D (E) |F |- !Aaug7 |A |C |E |G |- !Aaug7 |A |C |E (F) |G |- !Aaug7 |A |C (D) |E (F) |G |- !Baug7 |B |D |F |A |- !Baug7 |B |D |F (G) |A
See also Augmentation (music)
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