CadenzaB thirteenth, sharp eleven
B13(♯11)
Also written B13#11
E♯ is the key you know as F.
Everything the lydian dominant has: 9, ♯11 and 13. Those three tensions form a D♭ major triad — “upper structure II” — so pianists play it as D♭ over B7.
How pianists voice B13(♯11)
Nobody plays a jazz chord in root position. These are the shapes that actually get played — the same ones Cadenza shows when you play the chord.
Shell Left hand
1 · 3 · ♭7 — root, 3rd and 7th: the three notes that say what the chord is. Left hand, low; everything else is colour.
Rootless A From the 3rd
3 · 13 · ♭7 · 9 — no root: the bass player has it. The left-hand voicing of modern jazz piano.
Rootless B From the 7th
♭7 · 9 · 3 · 13 — the other half of the pair. A and B alternate through a ii–V–I so the hand barely moves. Without B underneath, the same keys read as Amaj7(♯11) — the bass turns them into B13(♯11).
Drop 2 Two hands
13 · 1 · 3 · ♭7 — close position with the second voice from the top dropped an octave: wider, warmer, the standard for chord melody.
Upper structure II Triad over shell
1 · 3 · ♭7 · 9 · ♯11 · 13 — a D♭ major triad in the right hand (9, ♯11 and 13) over the root, 3rd and ♭7 in the left. One familiar shape, all the tension.
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