The A♯ Augmented chord is a three-note chord made up of A♯, C♯♯, and E♯♯. It is built from a root, major third, and augmented fifth.
Construction
A♯ Augmented = Root + Major 3rd + Minor 6th = A♯ · C♯♯ · E♯♯
| Note | Interval | Degree |
|---|---|---|
| A♯ | Root | 1 |
| C♯♯ | Major 3rd | 3 |
| E♯♯ | Minor 6th | ♯5 |
A♯ Augmented Inversions
| Position | Notes |
|---|---|
| Root Position | A♯ – C♯♯ – E♯♯ |
| 1st Inversion | C♯♯ – E♯♯ – A♯ |
| 2nd Inversion | E♯♯ – A♯ – C♯♯ |
Key Signature
A Augmented chord is built from symmetrical or ambiguous intervals, so it doesn’t belong to a single key and has no key signature of its own.
Same Notes, Other Names
The notes A♯ – C♯♯ – E♯♯ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell the following:
A♯ Augmented — Frequently Asked Questions
What is the A♯ Augmented chord on piano?
The A♯ Augmented chord contains the notes A♯ – C♯♯ – E♯♯. On piano, play these notes together to sound the chord.
What notes are in the A# Augmented chord?
The A# Augmented chord contains three notes: A# (root), C## (major third), and E## (augmented fifth — one semitone higher than a perfect fifth). The augmented fifth is what gives this chord its tense, unresolved quality.
How does the A# Augmented chord differ from A# Major?
The only difference between A# Augmented and A# Major is the fifth: A# Major has a perfect fifth, while A# Augmented raises it by one semitone to an augmented fifth (E##). This single change transforms a stable, resolved chord into one full of tension and forward motion.
What is the symbol for the A# Augmented chord?
The A# Augmented chord is written as A#aug or A#+. The "aug" or "+" symbol indicates the augmented fifth. In lead sheets and chord charts, both notations are common — A#aug appears in classical and jazz contexts while A#+ is common in pop and rock.
How do I use the A# Augmented chord in music?
Augmented chords create tension and a sense of motion. The most common uses are: (1) as a chromatic passing chord between the I and IV chords (e.g., A# → A#aug → IV), (2) over a chromatic bass line moving upward, and (3) in jazz as a substitute for dominant chords. The augmented fifth wants to resolve up by one semitone.
What are the inversions of the A# Augmented chord?
The A# Augmented chord has a unique property: all three of its inversions are enharmonically equivalent. Because each note is separated by exactly 4 semitones (a major third), rotating the notes always produces the same interval structure. A#aug in root position, first inversion, and second inversion all sound the same quality.
What songs use augmented chords?
Augmented chords appear in Oh! Darling (Beatles), which uses Aaug as a chromatic passing chord, and in many jazz standards as chromatic dominant substitutes. Stevie Wonder and Elton John frequently use augmented chords for their characteristic tension-building quality.