B♭ 7th suspended 4th chord on bass (B♭7sus4)

Also called or written B♭7sus4, B♭ or B♭ Dominant 7th Suspended 4th

B♭ 7th suspended 4th contains B♭, E♭, F, and A♭. The 6th-fret shape demands a wide stretch, and the 1st-fret inversion requires a full barre.

6frB♭FA♭E♭EADG
Positions on the neck1 of 3
Practice B♭ 7th suspended 4th chord

How it is built

B♭RootE♭Perfect fourthFPerfect fifthA♭Minor seventh

Formula 1, 4, 5, ♭7

Inversions
  • Root positionB♭–E♭–F–A♭B♭7sus46-8-6-8
  • First inversionE♭–F–A♭–B♭B♭7sus4/E♭no shape on this instrument
  • Second inversionF–A♭–B♭–E♭B♭7sus4/F1-1-1-1
  • Third inversionA♭–B♭–E♭–FB♭7sus4/A♭no shape on this instrument

How do you play a B♭ 7th suspended 4th chord on bass?

B♭ 7th suspended 4th is played at the 6th fret as 6 8 6 8: index finger on the E string at fret 6, ring finger on the A string at fret 8, middle finger on the D string at fret 6 and pinky finger on the G string at fret 8.

Full note and interval breakdown
StringFretFingerNote
4 (E)61B♭ (1)
3 (A)83F (5)
2 (D)62A♭ (♭7)
1 (G)84E♭ (4)

AdvancedThe 1st-fret inversion requires barring all four strings cleanly while keeping the bass note F clear.

B♭7sus4/F inversion · fret 1

B♭ 7th suspended 4th is played at the 1st fret as 1 1 1 1: barre your index finger across fret 1.

Full note and interval breakdown
StringFretFingerNote
4 (E)11 (barre)F (5)
3 (A)11 (barre)B♭ (1)
2 (D)11 (barre)E♭ (4)
1 (G)11 (barre)A♭ (♭7)

B♭7sus4/F inversion · fret 13

B♭ 7th suspended 4th is played at the 13th fret as 13 13 13 13: barre your index finger across fret 13.

Full note and interval breakdown
StringFretFingerNote
4 (E)131 (barre)F (5)
3 (A)131 (barre)B♭ (1)
2 (D)131 (barre)E♭ (4)
1 (G)131 (barre)A♭ (♭7)

Why it sounds like that

B♭ 7th suspended 4th is built from the formula 1, 4, 5, ♭7. The perfect 4th between B♭ and E♭ creates the suspended sound, while the minor 7th A♭ adds tension. Compare it to B♭ suspended 4th, which has only three notes.

What goes wrong with B♭ 7th suspended 4th?

  • Letting the ring finger lean on the D string, which mutes the 6th-fret note.
  • Pressing the barre unevenly in the inversion, causing the outer strings to buzz.

When to use it

B♭ 7th suspended 4th functions as the V chord in E♭ major, heard in the I–IV–V–I progression E♭ major–A♭ major–B♭ major–E♭ major. It fits blues and rock bass lines that need a suspended dominant. Compare it to B♭ minor to hear the difference between a suspended dominant and a minor chord.

Changing to and from B♭ 7th suspended 4th

  • Sliding the shape down one fret to the 5th fret gives A 7th suspended 4th.
  • Sliding the shape up one fret to the 7th fret gives B 7th suspended 4th.

Which voicing to use

The 6th-fret shape keeps B♭ in the bass for a strong root position. The B♭7sus4/F inversion at the 1st fret puts F in the bass, which gives a softer, less grounded feel.

Other B♭ chords

Common questions

How is B♭ 7th suspended 4th written?

B♭ 7th suspended 4th is written B♭7sus4, and the root is also spelled Bb in ASCII. It is also known as Dominant 7th Suspended 4th. It is also spelled A♯ in enharmonic notation for the same sounding root.

Can B♭ 7th suspended 4th be played without a barre?

Yes, the 6th-fret shape uses individual fingers. The 1st-fret inversion requires a barre across all four strings.

What is the hardest part of the 1st-fret inversion?

Keeping the barre even so every string rings clearly. The bass note F must sound cleanly without buzzing.