The C♭ Augmented 7th chord is a four-note chord made up of C♭, E♭, G, and B♭♭. It is built from a root, major third, augmented fifth, and minor seventh.
Construction
C♭ Augmented 7th = Root + Major 3rd + Minor 6th + Minor 7th = C♭ · E♭ · G · B♭♭
| Note | Interval | Degree |
|---|---|---|
| C♭ | Root | 1 |
| E♭ | Major 3rd | 3 |
| G | Minor 6th | ♯5 |
| B♭♭ | Minor 7th | ♭7 |
C♭ Augmented 7th Inversions
| Position | Notes |
|---|---|
| Root Position | C♭ – E♭ – G – B♭♭ |
| 1st Inversion | E♭ – G – B♭♭ – C♭ |
| 2nd Inversion | G – B♭♭ – C♭ – E♭ |
| 3rd Inversion | B♭♭ – C♭ – E♭ – G |
Key Signature
A Augmented 7th 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 C♭ – E♭ – G – B♭♭ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
C♭ Augmented 7th — Frequently Asked Questions
What is the C♭ Augmented 7th chord on piano?
The C♭ Augmented 7th chord contains the notes C♭ – E♭ – G – B♭♭. On piano, play these notes together to sound the chord.
What notes are in the Cb Augmented 7th chord?
The Cb Augmented 7th chord (Cb+7) contains four notes: Cb (root), Eb (major third), G (augmented fifth), and Bbb (minor seventh, enharmonically A). This is the enharmonic equivalent of B+7.
How does Cb Augmented 7th differ from Cb Dominant 7th?
Both contain Cb, Eb, and Bbb. Cb+7 has G (augmented fifth) while Cb7 has Gb (perfect fifth). The raised fifth adds chromatic tension.
How is Cb Augmented 7th used in music?
Cb+7 is the enharmonic equivalent of B+7, resolving to Fb/E Major. In practice, musicians use B+7. The Cb spelling appears in extreme flat-key theoretical contexts.
What genres use Augmented 7th chords?
Augmented 7th chords are common in jazz, gospel, blues, and R&B. Whether spelled Cb+7 or B+7, the sound is identical.
What songs use Augmented 7th chords?
Augmented 7th chords appear in jazz standards and gospel. Cb+7/B+7 resolves to E Major.
What is the difference between +7 and 7#5?
They are the same chord. Cb+7, Cb7#5, and Cbaug7 all refer to Cb Augmented 7th.