C major thirteenth

Cmaj13

Also written CM13 · CΔ13

NotesC · E · G · B · D · A
Formula1 · 3 · 5 · 7 · 9 · 13
C1E3G5B7D9A13
All its notes, from the root

The major 7th with 9 and 13 added: every note of C major except the 4th, which would clash with the 3rd. A tonic — the fullest one there is.

How pianists voice Cmaj13

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

E3A13B7D9

3 · 13 · 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 E7sus4 — the bass turns them into Cmaj13.

Rootless B From the 7th

B7D9E3A13

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 C underneath, the same keys read as Bm11 — the bass turns them into Cmaj13.

Drop 2 Two hands

A13C1E3B7

13 · 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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