CadenzaB seventh, sharp nine
B7(♯9)
Also written B7+9 · B7#9
C𝄪 is the key you know as D.
Major 3rd and minor 3rd at once: the ♯9 (C𝄪) is the minor 3rd written as a tension. The “Hendrix chord”, the blues' favourite dominant, and in jazz a V of E minor.
How pianists voice B7(♯9)
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 · 5 · ♭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 · 5 — the other half of the pair. A and B alternate through a ii–V–I so the hand barely moves.
Drop 2 Two hands
5 · 1 · 3 · ♭7 — close position with the second voice from the top dropped an octave: wider, warmer, the standard for chord melody.
Hendrix voicing Guitar shape
1 · 3 · ♭7 · ♯9 — root low, then 3rd, ♭7 and the ♯9 on top, so major and minor 3rd ring together. Jimi Hendrix made it famous on E.
Seventh, sharp nine chords in every key
Every B chord
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