The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped.
B13 is B, D#, F#, A, C# and G# — B9 with the thirteenth added on top.
It sounds big and open. Six notes will not fit under four fingers: the fifth goes first, then the ninth, and the third, flat seventh and thirteenth stay.

| B | D# | F# | A | C# | G# |
|---|---|---|---|---|---|
| 1 | 3 | 5 | ♭7 | 9 | 13 |
Dominant — the full V chord.
Also written Bdom13 or B dominant 13. The same chord either way; which spelling you meet depends on who wrote the chart.
The same operation one voice further down: the third voice from the top falls an octave and becomes the bass.
That leaves a bigger hole under the top three notes, so a string gets skipped: the muted string in the middle is the shape, not a mistake.
B13 has 8 of them, on strings 6-4-3-2 and strings 5-3-2-1, from open position up to the 11th — every inversion the chord has: B in the bass, D# in the bass, A in the bass and G# in the bass. The one to learn first is the G# shape at the nut.
4 of them sit on strings 6-4-3-2, so you can run the inversions up one set without changing strings — which is the whole reason to learn them as a family rather than as separate grips.
Start with x21244 — no barre and down at the nut. None of the shapes for B13 uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 6 of the 7 need a barre. Together they cover the neck from the 1st fret to the 9th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| x21244 | 1st fret | B, root position | G# | all fretted |
| x21224 | 1st fret | B, root position | G# | barred |
| 222244 | 2nd fret | F#, 2nd inversion | G# | barred |
| 746445 | 4th fret | B, root position | A | barred |
| 766675 | 5th fret | B, root position | A | barred |
| 777899 | 7th fret | B, root position | C# | barred |
| 797897 | 7th fret | B, root position | B | barred |
The same notes rebuilt from scratch give 2 shell, 13 drop 2 and 24 rootless voicings, each on its own page.
Tensions. A shell of B13, root, third and seventh, leaves a string free, and the tones that belong over it are the #11 (E#).
B13 is the V of E, and that is where it goes if it goes anywhere: the third and the flat seventh are a tritone apart, and both resolve by a semitone into E.
Voice by voice, B13 → E. 2 voices move by a semitone, and 2 notes are common to both chords.
| In B13 | Moves | In E |
|---|---|---|
| B, the root | stays where it is | B, the fifth |
| D#, the major third | rises a semitone | E, the root |
| F#, the fifth | falls a whole tone | E, the root |
| A, the flat seventh | falls a semitone | G#, the major third |
| C#, the ninth | falls a whole tone | B, the fifth |
| G#, the thirteenth | stays where it is | G#, the major third |
In which keys. Every note of B13 belongs to C# minor (the ♭VII) and E major (the V, the dominant).
Every note of B13 is in B mixolydian and B lydian dominant.
Change one note of B13 and you have Bmaj13 (the flat seventh becomes a major seventh), B69 (drop the flat seventh), B9 (drop the sixth) or B9#11 (the sixth becomes a flat fifth).
B13 is a dominant chord — root, major third, fifth, minor seventh. Dominant seventh chords on every root.
On B13’s sound and use this page follows Ted Pease & Ken Pullig, Modern Jazz Voicings (Berklee Press, 2001). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.