semicord

A11 A dominant eleventh chord

Notes
A C# E G B D
Formula
1 3 5 b7 9 11
Semitones
0 4 7 10 14 17 above the root
Other symbols
Adom11

A to C# is a major third (4 semitones), C# to E is a minor third (3 semitones), E to G is a minor third (3 semitones), G to B is a major third (4 semitones), B to D is a minor third (3 semitones). All six notes stacked in thirds, 1 3 5 b7 9 11. The eleventh, D, sits a minor ninth above the third C# and clashes with it, so in practice the third is left out: A E G B D is how A11 is usually played, the same notes as A9sus4. Leave out the fifth as well and the engine hears G/A instead (A G B D), so the guitar shapes here keep E.

A11 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C6D6E6F6G6A6B6C#4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5C#6Eb6F#6Ab6Bb6C4AC5C#EGBC6D

Root position from A4: A4, C#5, E5, G5, B5, D6. Middle C is C4.

A11 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 A as its lowest note.

×ADGBE
Open position (A-shape)
x 0 0 0 0 0 (low E to high e)
Sounds A2 D3 G3 B3 E4, third left out
5frAADDGGDDEEBB
E-shape barre, root on the E string at fret 5
5 5 5 7 5 7 (low E to high e)
Sounds A2 D3 G3 D4 E4 B4, third left out

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 dominant eleventh chords on other roots.

Inversions of A11

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 positionA C# E G B DA11
1st inversionC# E G B D AA11/C#
2nd inversionE G B D A C#A11/E
3rd inversionG B D A C# EA11/G
4th inversionB D A C# E GA11/B
5th inversionD A C# E G BA11/D

Where A11 fits

A11 is V11 in D major. The eleventh, D, is the same note as the fourth of a sus chord and wants to fall to the third C#; that is why the third is usually left out, and why A11 works as a softer V that delays the pull home. It often moves to A7 before the tonic.