C major ninth

Cmaj9

Also written CM9 · CΔ9

NotesC · E · G · B · D
Formula1 · 3 · 5 · 7 · 9
C1E3G5B7D9
All its notes, from the root

The major 9th: a tonic with the 9th on top, lush but stable. Without its root it is Em7 — a minor 7th built on the 3rd — which is the quickest way to find it on the keyboard.

How pianists voice Cmaj9

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

C1E3B7

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

E3G5B7D9

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 Em7 — the bass turns them into Cmaj9.

Rootless B From the 7th

B7D9E3G5

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

G5C1E3B7

5 · 1 · 3 · 7 — close position with the second voice from the top dropped an octave: wider, warmer, the standard for chord melody.

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