Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top.
B69 is B, D#, F#, G# and C# — B6 with the ninth added as well.
It sounds wide and entirely at rest. The modern way to voice a tonic when a triad is too bare and a maj7 too pointed.

| B | D# | F# | G# | C# |
|---|---|---|---|---|
| 1 | 3 | 5 | 6 | 9 |
Tonic — it commits to nothing.
Also written B6/9, B6add9 or B six nine. The same chord either way; which spelling you meet depends on who wrote the chart.
Root, third and seventh. The third and seventh, the guide tones, are what make the chord major, minor or dominant, so the fifth can go: it says nothing the symbol needs.
Three notes means a spare string, which is the real point. Put a tension on it.
B69 has 4 of them, on the middle four strings, the bottom four strings and the top four strings, from open position up to the 13th — all in one inversion, so the bass note never moves. The one to learn first is the B shape at the nut, which is the easiest grip here.
Start with x-14-11-13-12-11 — no barre. None of the shapes for B69 uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 7 of the 8 need a barre. Together they cover the neck from the 1st fret to the 14th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| x21122 | 1st fret | B, root position | F# | barred |
| x44444 | 4th fret | C#, 9th in the bass | G# | barred |
| 766677 | 6th fret | B, root position | B | barred |
| xx9899 | 8th fret | B, root position | C# | barred |
| x99899 | 8th fret | F#, 2nd inversion | C# | barred |
| x-11-11-11-12-11 | 11th fret | G#, 6th in the bass | D# | barred |
| x-14-11-13-12-11 | 11th fret | B, root position | D# | all fretted |
| x-14-13-13-14-14 | 13th fret | B, root position | F# | barred |
The same notes rebuilt from scratch give 13 drop 2, 8 drop 3 and 13 rootless voicings, each on its own page.
Tensions. A shell of B69, root, third and seventh, leaves a string free, and the tones that belong over it are the #11 (E#).
How you get to it. The turn that lands on B69 is C#m7 to F#7 — the ii and the V of B — and F#7 shares its third and seventh with C#m7, so the hand barely moves between them.
In which keys. Every note of B69 belongs to C# minor (the ♭VII), Eb minor (the ♭VI), E major (the V), F# major (the IV), Ab minor (the ♭III) and B major (the I).
B69 is every note of the B major pentatonic, and nothing else. It also sits inside B major, B lydian, B mixolydian and B lydian dominant.
Change one note of B69 and you have Bmaj9 (the sixth becomes a major seventh), Bmaj13 (add the major seventh), Bm69 (the major third becomes a minor third), Badd9 (drop the sixth), B6 (drop the ninth) or B9 (the sixth becomes a flat seventh).
B69 is a major chord — root, major third, fifth. Major chords on every root.
On B69’s sound and use this page follows Mark Levine, The Jazz Piano Book (Sher Music, 1989). 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.