CadenzaA dominant thirteenth
A13
Also written A7(13) · Adom13
The dominant 13th: 1–3–♭7–9–13, with the 5th and the 11th usually left out. V of D major. In a rootless voicing the 13th (F♯) stands where the 5th would be — that one note is the whole difference between A9 and A13.
How pianists voice A13
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 · 13 · ♭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 · 13 — the other half of the pair. A and B alternate through a ii–V–I so the hand barely moves. Without A underneath, the same keys read as Gmaj7(♯11) — the bass turns them into A13.
Drop 2 Two hands
13 · 1 · 3 · ♭7 — close position with the second voice from the top dropped an octave: wider, warmer, the standard for chord melody.
Dominant thirteenth chords in every key
Every A chord
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