C#9

C#9 is C#, E#, G#, B and D#, a dominant ninth. The shape this page opens on is written x43444, lowest string first.

Also written C#dom9 or C# dominant 9. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 8 common shapes for C#9 on the guitar, and 36 derived voicings in 4 families.

In which keys. Every note of C#9 belongs to Eb minor (the ♭VII) and F# major (the V).

The common shapes, written lowest string first: x43444, x66667, 966867, 9898xx, 9-11-9-8-9-11, 9-11-9-10-9-11, x-x-11-10-12-11, 13-x-11-13-12-11.

Shell. Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top. C#9 has x4344x, 9898xx, x-x-11-10-12-11.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. C#9 has x4344x, 9898xx, x-x-11-10-12-11, 1414xx, xx1421, xx3647, 7636xx, x6966x.

Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. C#9 has x4x441, 1x142x, 7x364x, x6x667, 9x986x, x-8-x-8-12-9, 11-x-11-10-12-x, x-14-x-10-14-11.

Rootless. The root left to the bass player. Frees a finger for a tension. C#9 has xx1101, xx3444, x6646x, xx6867, x8989x, x-x-9-10-9-11, x-x-13-13-12-13, x2314x.

Tensions. A shell of C#9, root, third and seventh, leaves a string free, and the tones that belong over it are the #11 (F##), the b13 (A) and the 13 (A#).

The common shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.