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Fig. 1 · C9 on the keyboard

piano chord

C9

C1E3G5B♭♭7D9

A dominant seventh carrying a ninth on top.

on guitaron ukulelethe scale

What is true of it

C9 is C, E, G, B♭ and D — 1, 3, 5, b7 and 9 counted from C.

On an instrument that cannot reach all 5, the 5 and 1 go first, in that order.

C in other shapes

Cadd9added ninthCmaj9major ninthCm9minor ninthCmajorCmminorCdimdiminished

C♯9D♭9D9D♯9E♭9E9F9F♯9all 374