Bb Augmented
Introduction
Enharmonic equivalent: B♭ is enharmonically equivalent to A♯. See A# Augmented.
Notes
Bb Augmented Inversions
| Position | Notes |
|---|---|
| Root Position | Bb4 – D5 – F#5 |
| 1st Inversion | D5 – F#5 – Bb5 |
| 2nd Inversion | F#5 – Bb5 – D6 |
Key Signature
The key of Bb Augmented has 2 flats: B♭, E♭.
Theory: Intervals
The Bb Augmented is built by stacking intervals from the root note. The formula R-M3-A5 describes the scale degrees used. The intervals P1-M3-A5 show the distance between each note in the chord.
Bb Augmented — Frequently Asked Questions
What notes are in the Bb Augmented chord?
The Bb Augmented chord contains three notes: Bb (root), D (major third), and F# (augmented fifth — one semitone higher than a perfect fifth). The augmented fifth is what gives this chord its tense, unresolved quality.
How does the Bb Augmented chord differ from Bb Major?
The only difference between Bb Augmented and Bb Major is the fifth: Bb Major has a perfect fifth, while Bb Augmented raises it by one semitone to an augmented fifth (F#). This single change transforms a stable, resolved chord into one full of tension and forward motion.
What is the symbol for the Bb Augmented chord?
The Bb Augmented chord is written as Bbaug or Bb+. The "aug" or "+" symbol indicates the augmented fifth. In lead sheets and chord charts, both notations are common — Bbaug appears in classical and jazz contexts while Bb+ is common in pop and rock.
How do I use the Bb 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., Bb → Bbaug → 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 Bb Augmented chord?
The Bb 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. Bbaug 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.
Practice Tips
- Compare Bb Major and Bb Augmented back to back — press Bb–D–(perfect 5th) then Bb–D–F# to hear how the raised 5th creates tension.
- The augmented fifth (F#) wants to resolve upward by one semitone — practice Bbaug → resolving chord to feel this motion.
- All augmented chord inversions sound the same quality — explore this by playing root, first, and second inversions in sequence.
- Use Bbaug as a chromatic passing chord: Bb Major → Bbaug → (IV chord) to hear its most common musical function.
- Augmented chords divide the octave into three equal parts — Bbaug, Daug, and F#aug are all the same chord (enharmonic). Verify this by playing each.
- In jazz, try using Bbaug as a substitute for the V7 chord — the aug5 acts as a chromatic approach to the I chord's root.