# C♭ Augmented 7th piano chord (C♭aug7)

C♭aug7 contains C♭, E♭, G and B♭♭. An augmented triad with the minor seventh added on top. E♭ is a black key; C♭, G and B♭♭ are white.

- Canonical page: https://piano.org/chords/augmented-7th/c-flat/
- Entity: chord:augmented-7th:c-flat
- Notes: C♭ E♭ G B♭♭
- Formula: 1 3 ♯5 ♭7
- Intervals from root: P1, M3, m6, m7
- Interval stack (semitones): 4 4 2
- Also written: C♭aug7, Cbaug7, C♭ augmented 7th
- Parameters: A440, 12-TET, 165 mm octave, spans centre to centre

## Construction

| Degree | Note | Interval from root | Semitones |
| --- | --- | --- | --- |
| 1 | C♭ | Perfect unison | 0 |
| 3 | E♭ | Major third | 4 |
| ♯5 | G | Minor sixth | 8 |
| ♭7 | B♭♭ | Minor seventh | 10 |

## Fingering

Rest your right hand over the notes with finger 1 on C♭, finger 2 on E♭, finger 3 on G, finger 5 on B♭♭. The left hand mirrors it.
Right hand 1-2-3-5, left hand 5-3-2-1. Source: piano.org fingering method v1.

## Inversions

| Position | Bass | Notes in order | Figured bass | Span |
| --- | --- | --- | --- | --- |
| Root position | C♭ | C♭3 E♭4 G4 B♭♭4 | 7 | 10 st, 138 mm |
| First inversion (C♭aug7/E♭) | E♭ | E♭4 G4 B♭♭4 C♭4 | 6/5 | 8 st, 110 mm |
| Second inversion (C♭aug7/G) | G | G4 B♭♭4 C♭4 E♭5 | 4/3 | 8 st, 110 mm |
| Third inversion (C♭aug7/B♭♭) | B♭♭ | B♭♭4 C♭4 E♭5 G5 | 4/2 | 10 st, 138 mm |

## Voicings (10)

| Voicing | Notes | Span | Relation | Omits or adds |
| --- | --- | --- | --- | --- |
| Close, root position | C♭3 E♭4 G4 B♭♭4 | 10 st, 138 mm | identical | none |
| Close, first inversion | E♭4 G4 B♭♭4 C♭4 | 8 st, 110 mm | identical | none |
| Close, second inversion | G4 B♭♭4 C♭4 E♭5 | 8 st, 110 mm | identical | none |
| Close, third inversion | B♭♭4 C♭4 E♭5 G5 | 10 st, 138 mm | identical | none |
| Drop 2 | G3 C♭3 E♭4 B♭♭4 | 14 st, 193 mm | identical | none |
| Drop 3 | E♭3 C♭3 G4 B♭♭4 | 18 st, 248 mm | identical | none |
| Drop 2 and 4 | C♭2 G3 E♭4 B♭♭4 | 22 st, 303 mm | identical | none |
| Shell, root ♭7 3 | C♭2 B♭♭3 E♭4 | 16 st, 220 mm | subset | omits G |
| Guide tones, 3 and ♭7 | E♭4 B♭♭4 | 6 st, 83 mm | subset | omits C♭ and G |
| Rootless close | E♭4 G4 B♭♭4 | 6 st, 83 mm | subset | omits C♭ |

## One-edit neighbors

| Becomes | Edit | Changes | Common tones |
| --- | --- | --- | --- |
| C♭aug | 1 3 ♯5 | drops B♭♭ | 3 |
| C♭7 | 1 3 5 ♭7 | G becomes G♭ | 3 |
| C♭9 | 1 3 5 ♭7 9 | G becomes G♭, D♭ | 3 |
| C♭ | 1 3 5 | G, B♭♭ becomes G♭ | 2 |
| C♭maj7 | 1 3 5 7 | G, B♭♭ becomes G♭, B♭ | 2 |
| C♭m7 | 1 ♭3 5 ♭7 | E♭, G becomes E♭♭, G♭ | 2 |
| C♭m7♭5 | 1 ♭3 ♭5 ♭7 | E♭, G becomes E♭♭, G♭♭ | 2 |
| C♭7sus4 | 1 4 5 ♭7 | E♭, G becomes F♭, G♭ | 2 |
| C♭6 | 1 3 5 6 | G, B♭♭ becomes G♭, A♭ | 2 |
| C♭add9 | 1 3 5 9 | G, B♭♭ becomes G♭, D♭ | 2 |

## Set theory

- Absolute pitch classes: {11, 3, 7, 9}
- Relative pitch classes: [0, 4, 8, 10]
- Normal order: [7, 9, 11, 3]
- Prime form: (0248)
- Forte number: 4-24
- Interval vector: <020301>

## Frequencies (close root position)

| Note | MIDI | Frequency |
| --- | --- | --- |
| C♭3 | 59 | 246.94 Hz |
| E♭4 | 63 | 311.13 Hz |
| G4 | 67 | 392.00 Hz |
| B♭♭4 | 69 | 440.00 Hz |

## Questions and answers

### What notes are in C♭aug7?

C♭aug7 contains C♭, E♭, G and B♭♭. The formula is 1, 3, ♯5, ♭7.

### How do you play C♭aug7 on piano?

Play C♭, E♭, G and B♭♭ together. Right hand fingers 1, 2, 3, 5; left hand 5, 3, 2, 1. E♭ is a black key; C♭, G and B♭♭ are white.

### What are the inversions of C♭aug7?

4 positions: root position C♭ E♭ G B♭♭, C♭aug7/E♭, C♭aug7/G, C♭aug7/B♭♭.

### What is the difference between C♭aug7 and C♭aug?

Drops B♭♭. 3 of the notes are shared.

### What is an easy C♭aug7 for small hands?

The guide tones, 3 and ♭7 voicing, E♭4 B♭♭4, spans 6 semitones or about 83 mm.

### What are the frequencies of C♭aug7?

From C♭3 at A440 in 12-TET: 246.94, 311.13, 392.00, 440.00 Hz.

### What is the set class of C♭aug7?

Prime form (0248), Forte 4-24, interval vector &lt;020301&gt;.

### How do I transpose C♭aug7 to another key?

Keep the 1, 3, ♯5, ♭7 formula on the new root. Caug7 is C, E, G♯, B♭; D♭aug7 is D♭, F, A, C♭.

### Is Baug7 the same as C♭aug7?

Enharmonically yes: the same piano keys and the same sound, spelled differently.

## Provenance

Every derived value above is computed by the piano.org theory kernel from the root, the quality and the stated parameters. Nothing is hand-entered per chord.

Machine record: https://piano.org/api/knowledge/v1/entities/chord:augmented-7th:c-flat
Last reviewed: 2026-08-12