C♯13
C♯ Dominant 13th
1 3 5 ♭7 9 13

Notes in C♯13

C♯R
F3
A♭5
B♭7
E♭9
B♭13

The C♯13 chord contains 6 notes: C♯, F, A♭, B, E♭, B♭

Intervals

IntervalSemitonesNoteFunction
R0C♯Root
34FMajor 3rd
57A♭Perfect 5th
♭710BMinor 7th
92E♭Major 9th
139B♭Major 13th

About C♯ Dominant 13th Chords

Dominant 13th chords are the largest standard chord, potentially containing all seven notes of the scale. Guitarists typically voice them selectively — root, 3rd, 7th, and 13th are the essential tones. They're smooth, jazzy, and sophisticated.

Compatible Scales & Modes

These scales contain all the notes of C♯13 and can be used for soloing, improvising, and writing melodies over this chord.

C♯ Mixolydian
Contains all chord tones including the 13th (6th).
C♯ Lydian Dominant
Mixolydian with ♯4 — common in jazz over dominant 13th chords.

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Playing C# thirteenth on Guitar

The C# thirteenth chord, spelled C♯, F, A♭, B, E♭, B♭, occupies a specific harmonic role that depends on the musical context. In the key of Db major enharmonically, this chord can function as a primary harmony or as a passing color depending on where it appears in the progression. Understanding which scale degrees produce C#-rooted chords helps you predict chord progressions and improvise melodies that complement the harmony.

On guitar, C# thirteenth voicings benefit from fourth-fret barre shapes that provide a bright, cutting tone. The physical shape of this chord on the fretboard determines its tonal character — the same notes arranged in different voicings produce noticeably different sounds due to string gauge, fret position, and overtone content. Experiment with playing C# thirteenth in multiple positions to find the voicing that best fits the register and texture of the music you are working on.

The thirteenth extension in C#13 adds the highest practical chord tone, producing sophisticated harmony favored in jazz comping. Despite containing up to seven notes theoretically, practical C#13 guitar voicings use four or five strings with strategic note omissions.

When practicing C# thirteenth, use the compatible scales listed above to improvise melodies and riffs. Start by playing the chord, then explore the scale tones one at a time to hear how each note sounds against the harmony. This ear training exercise connects your theoretical knowledge of C#-rooted chords to practical musicianship skills that improve your playing across all genres and styles.