Bb7sus4 Bb seventh suspended fourth chord
- Notes
- Bb Eb F Ab
- Formula
- 1 4 5 b7
- Semitones
- 0 5 7 10 above the root
- Also written
- A#7sus4 (A# D# E# G#)
- Other symbols
- Bb7sus
Bb to Eb is a perfect fourth (5 semitones), Eb to F is a major second (2 semitones), F to Ab is a minor third (3 semitones). A dominant seventh with the fourth, Eb, in place of the third. Like any sus chord it is neither major nor minor. With Ab in the bass the same four keys read as Bb7sus4/Ab.
Bb7sus4 on the piano
Root position from Bb4: Bb4, Eb5, F5, Ab5. Middle C is C4.
Bb7sus4 on the guitar
Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has Bb as its lowest note.
x 1 3 1 4 1 (low E to high e)
Sounds Bb2 F3 Ab3 Eb4 F4
6 8 6 8 6 6 (low E to high e)
Sounds Bb2 F3 Ab3 Eb4 F4 Bb4
The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play seventh suspended fourth chords on other roots.
Inversions of Bb7sus4
An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.
| Position | Notes, bass first | Named | Listen |
|---|---|---|---|
| Root position | Bb Eb F Ab | Bb7sus4 | |
| 1st inversion | Eb F Ab Bb | Bb7sus4/Eb | |
| 2nd inversion | F Ab Bb Eb | Fm11 (also read as Bb7sus4/F) | |
| 3rd inversion | Ab Bb Eb F | Bb7sus4/Ab |
Where Bb7sus4 fits
Bb7sus4 is V7sus4 in Eb major. The usual move is Bb7sus4 → Bb7: the fourth, Eb, falls a half step to the third D while the seventh Ab stays. In modal jazz and gospel it is often left unresolved.