The A 7♭5 chord is a four-note chord made up of A, C♯, E♭, and G. It is built from a root, major third, diminished fifth, and minor seventh.
Construction
A 7♭5 = Root + Major 3rd + Diminished 5th + Minor 7th = A · C♯ · E♭ · G
| Note | Interval | Degree |
|---|---|---|
| A | Root | 1 |
| C♯ | Major 3rd | 3 |
| E♭ | Diminished 5th | ♭5 |
| G | Minor 7th | ♭7 |
A 7♭5 Inversions
| Position | Notes |
|---|---|
| Root Position | A – C♯ – E♭ – G |
| 1st Inversion | C♯ – E♭ – G – A |
| 2nd Inversion | E♭ – G – A – C♯ |
| 3rd Inversion | G – A – C♯ – E♭ |
Key Signature
A chord has no key signature of its own, but the A 7♭5 is the tonic (I) chord of A Major, whose key signature has 3 sharps (F♯, C♯, G♯).
F♯C♯G♯
Order of sharps
Sharps are added to a key signature in a fixed order. Each new sharp key adds the next sharp on the list.
F♯C♯G♯D♯A♯E♯B♯
Mnemonic: Father Charles Goes Down And Ends Battle
Chords in the Key of A Major
These are the triads built on each degree of the A major scale:
Same Notes, Other Names
The notes A – C♯ – E♭ – G aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
A 7♭5 — Frequently Asked Questions
What is the A 7♭5 chord on piano?
The A 7♭5 chord contains the notes A – C♯ – E♭ – G. On piano, play these notes together to sound the chord.
What notes are in the A 7♭5 chord?
The A 7♭5 chord (A7♭5) contains 4 notes: A, C#, Eb, G. Formula: R-M3-d5-m7.
How is A7♭5 used in music?
A7♭5 is used in jazz, fusion, and contemporary music to add harmonic color. It appears as a dominant or tonic chord depending on context.
What is the scale degree formula for A7♭5?
A7♭5 uses scale degrees 1-3-b5-b7, giving it its distinctive sound.