Bbaug

Q: What notes are in the Bbaug chord?

The Bbaug chord (Bb Augmented) contains: Bb, D, F#. Its interval structure is shown above in the Theory section.

Q: How do I build Bbaug on the keyboard?

Take the root and add the remaining chord tones following the interval formula. The highlight shows chord content, while the inversion control changes which chord tone is in the bass.

Q: Which keys is Bbaug found in?

The chord acts as a diatonic degree in several keys — they are marked on the circle of fifths in the "Harmonic context" block.

Q: What can I substitute for Bbaug?

A substitution depends on harmonic function and voice leading, not only on shared tones. Computed options appear in the "Substitutions" block and should be checked in context.

Bb Augmented

Octaves

Musical context

ChordBbaugBb Augmented

ArpeggioBb majorBroken triad

ScaleBb major7 notes

KeyBb majorMajor key

ProgressionPop axisSequence

How the chord relates to the scale, mode, key and progression.

Theory

General info

Full name: Bb Augmented
Symbol: Bbaug
Root: Bb
Quality: Augmented

Chord notes

1Bbroot

3Dmajor 3rd

#5F#aug 5th

Functions & resolutions

Stability / tension: Marked tension — unstable, seeks resolution
Most common resolutions: BbBb Major EbEb Major
Unstable degrees: #5Gb
6G
resolves up to the 6th
Main resolution: Bbaugsource
BbBb Major
Augmented Bbaug has a raised 5th. As a dominant it resolves up a 4th — the raised 5th rising a semitone. Returning to the major of the same root, it instead falls back to a perfect 5th.
Other resolutions: Bbaugsource
Deceptive resolution
BbmBb Minor
An augmented chord can resolve to the minor chord of the same root: the raised 5th falls to a perfect 5th and the major 3rd lowers to a minor 3rd.
Bbaugsource
No resolution needed
In a whole-tone context, the augmented chord can be used as a color chord — without mandatory resolution.
Bbaugsource
Jazz reharmonization
EbEb Major
In jazz, aug often acts as a dominant with raised 5th, resolving up a 4th as a V7 substitute.
Bbaugsource
Functional resolution
DD Major
Due to its symmetry (equal intervals), an augmented chord can resolve to chords a major 3rd apart.

Gmharmonic minor

Bbaugdegree III

The raised 7th of harmonic minor makes the III triad augmented — Bbaug arises within the key on its own.

BbaugV+

Ebresolution

As a dominant it resolves a fourth up: the raised fifth (F#) rises a semitone into the tonic's third (G).

Features

Character: Augmented, symmetric and unstable
Characteristic interval: Augmented 5th (#5)
Description: The augmented fifth (#5) is raised a semitone above normal. The chord is symmetric — all three notes are equidistant by major thirds.
Application: Chromatic passing
III in harmonic minor
Unexpected colors

Voicing & structure

Root position

v1Bb(Bb4)Bass

root

v2D(D5)M3from Bb

v3F#(F#5)M3from D

Harmony

Compatible scales

All chord tones are contained in these scales — use them for improvisation.

ScaleD Whole tone scale ScaleD Augmented scale ScaleF# Whole tone scale ScaleF# Augmented scale ScaleA# Whole tone scale ScaleA# Augmented scale ScaleC Whole tone scale ScaleD# Augmented scale ScaleE Whole tone scale ScaleG Augmented scale

This chord on guitar 🎸

See how Bbaug looks on guitar.

Explore

Circle of fifths

Highlighted major keys contain this chord among their diatonic harmonies.

Relative key: GmG minor
Dominant: FF major
Subdominant: EbEb major
Key signature: 2 flats (Bb, Eb)

What to learn next

ScaleBb Chromatic scaleScale to improvise over this chord ChordBb MajorA nearby chord on the same root — compare the sound PracticeChord trainerLock the fingering into muscle memory ProgressionChord progressionsHow this chord works inside real progressions ChordBb Dominant 7Another related chord to practise

Recommended for you

Bb MajorA chord that sounds close

Bb Dominant 7A chord that sounds close

Bb Chromatic scaleA scale related to this chord

Bb Persian scaleA scale related to this chord

Bb ByzantineA scale related to this chord

Practice

Keyboard Trainer

Reinforce it in practice — play and name notes on the interactive keyboard.

Open Trainer

Test yourself

(Press any key to start)

What notes are in the Bbaug chord?

How do I build Bbaug on the keyboard?

Which keys is Bbaug found in?

What can I substitute for Bbaug?