CadenzaC dominant ninth
C9
Also written C7(9) · Cdom9
The dominant ninth — what a jazz pianist plays on a plain C7 without being asked. V of F major. Leave out the root and the four notes left are Eø7: the rootless C9 is exactly that chord.
How pianists voice C9
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. Without C underneath, the same keys read as Eø7 — the bass turns them into C9.
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.
Dominant ninth chords in every key
Every C chord
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