CadenzaC six-nine
C6/9
Also written C69 · C6add9
The major 6 with the 9th added. There is no 7th to pull anywhere, so it is the jazz tonic when Cmaj7 sounds too sweet — and every note belongs to the C major pentatonic scale.
How pianists voice C6/9
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 · 6 — root, 3rd and 6th: the three notes that say what the chord is. Left hand, low; everything else is colour.
Rootless A From the 3rd
3 · 5 · 6 · 9 — no root: the bass player has it. The left-hand voicing of modern jazz piano. Without C underneath, the same keys read as Em11 — the bass turns them into C6/9.
Rootless B From the 6th
6 · 9 · 3 · 5 — the other half of the pair. A and B alternate through a ii–V–I so the hand barely moves. Without C underneath, the same keys read as A7sus4 — the bass turns them into C6/9.
Drop 2 Two hands
5 · 1 · 3 · 6 — close position with the second voice from the top dropped an octave: wider, warmer, the standard for chord melody.
In fourths Quartal
1 · 3 · 6 · 9 · 5 — 3, 6, 9 and 5 stacked a perfect 4th apart over the root. Open, modern, and not one note that could clash.
Six-nine chords in every key
Every C chord
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