Chords
Ab Augmented seventh
Ab · C · E · Gb
A dominant seventh with a raised fifth — an augmented triad with a seventh on top.
Also written Ab+7 · Ab7+ · Ab7aug · Abaug7
Ab Augmented seventh
Ab · C · E · Gb
Voicings on the piano
| Voicing | Notes | Play it on your instrument |
|---|---|---|
| Closed, root position | Ab3 · C4 · E4 · Gb4 | |
| Open (drop 2) | E3 · Ab3 · C4 · Gb4 | |
| Shell | Ab3 · C4 · Gb4 | |
| Rootless | C3 · E3 · Gb3 |
Tap a key or a fret to hear it.
Anatomy
Ab Augmented seventh (Ab7#5) contains the notes Ab · C · E · Gb, each with a role measured as an interval from the root.
Read on: how triads are built · seventh chords
Inversions
An inversion of Ab Augmented seventh puts a chord tone other than Ab in the bass; the name after the slash is that bass note.
Where it lives
The keys and the scales Ab Augmented seventh belongs to.
In which keys
Ab Augmented seventh is diatonic to 1 key; the numeral is its degree and the label its harmonic function.
- C# minorV+7#5Dominant
Scales that contain it
Ab Augmented seventh fits inside these scales, each built on Ab.
- Ab Whole ToneAb · Bb · C · D · E · F#
- Ab Mixolydian b6Ab · Bb · C · Db · Eb · Fb · Gb
- Ab Leading Whole ToneAb · Bb · C · D · E · Gb · G
- Ab Lydian MinorAb · Bb · C · D · Eb · Fb · Gb
- Ab Messiaen's Mode #6Ab · Bb · C · Db · D · E · F# · G
- Ab Messiaen's Mode #3Ab · Bb · Cb · C · D · Eb · Fb · Gb · G
Understanding the Ab Augmented seventh chord
Names and symbols
Ab7#5 is the chord symbol for Ab Augmented seventh; it is also written Ab+7, Ab7+, Ab7aug, Abaug7.
7♯5, +7 and aug7 usually all mean this chord: a dominant seventh on an augmented triad. Some books use aug7 for the major seventh on the augmented triad instead, so check which seventh a chart intends.
How it is built
On Ab it is Ab · C · E · Gb, stacking 1P · 3M · 5A · 7m. Raising the fifth turns the underlying triad augmented and makes the chord symmetrical in its lower three notes.
How it is used
The raised fifth is a semitone above the natural one, so it leans harder toward the tonic. It is a standard altered dominant, especially heading into a minor chord, and it fits the whole-tone scale exactly.
Learn this properly
Chapter 17: Theory in StylesCommon questions
- What notes are in Ab7#5?
- Ab7#5 contains Ab · C · E · Gb. Name any set of notes with the chord identifier.
- What scale fits a 7♯5 chord?
- The whole-tone scale, which contains the root, major third, augmented fifth and minor seventh exactly.
- Is 7♯5 the same as 7♭13?
- The same pitch, different function. ♯5 replaces the fifth; ♭13 is added above a chord that still has its natural fifth.
- What notes are in the Ab Augmented seventh chord?
- The Ab Augmented seventh chord contains the notes Ab · C · E · Gb: the root Ab with the intervals 1P, 3M, 5A, 7m stacked above it. Play them together for the chord or one after another for an arpeggio. The lowest note is normally Ab, but any chord tone can take the bass in an inversion.
- What intervals make up the Ab Augmented seventh chord?
- Measured from Ab, the Ab Augmented seventh chord stacks the intervals 1P, 3M, 5A, 7m. The quality of the third and of the seventh, if there is one, is what gives the chord its character; the rest of the notes colour it. Every interval in the formula links to its own page, with its sound.