semicord

Bb6 Bb major sixth chord

Notes
Bb D F G
Formula
1 3 5 6
Semitones
0 4 7 9 above the root
Also written
A#6 (A# C## E# F##)
Other symbols
BbM6, Bbmaj6

Bb to D is a major third (4 semitones), D to F is a minor third (3 semitones), F to G is a major second (2 semitones). A major triad plus the major sixth, G, nine semitones above Bb. With G in the bass the same four keys read as Gm7: which name fits depends on the bass note.

Bb6 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5C4BbC5DFG

Root position from Bb4: Bb4, D5, F5, G5. Middle C is C4.

Bb6 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.

×BbBbFFBbBbDDGG
A-shape, root on the A string at fret 1
x 1 3 3 3 3 (low E to high e)
Sounds Bb2 F3 Bb3 D4 G4
5frBbBb×GGDDFF×
E-shape, root on the E string at fret 6
6 x 5 7 6 x (low E to high e)
Sounds Bb2 G3 D4 F4

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 major sixth chords on other roots.

Inversions of Bb6

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.

PositionNotes, bass firstNamedListen
Root positionBb D F GBb6
1st inversionD F G BbGm7/D (also read as Bb6/D)
2nd inversionF G Bb DGm7/F (also read as Bb6/F)
3rd inversionG Bb D FGm7 (also read as Bb6/G)

Where Bb6 fits

Bb6 is I6 in Bb major, IV6 in F major. As a final tonic chord it is the swing-era and early rock and roll alternative to Bbmaj7: the sixth, G, adds colour without the half-step rub between Bb and a major seventh.