Also written Cadd9, C or C Add 9th
C add 9 is built from C, E, G, and D. This advanced voicing uses three open strings, creating a resonant, ringing sound.
The same three notes, with a different one in the bass.
C add 9 adds the ninth, D, to a C major triad: 1, 3, 5, 9. The ninth adds a gentle color without altering the major quality. Contrast with C major, which has only C, E, and G.
C add 9 is a tonic color in C major, often in the I–IV–V–I progression: C major–F major–G major–C major. It fits folk, pop, and ambient music where open strings ring out.
The Cadd9/E inversion places E in the bass, giving a warm, grounded sound. Use it when you want the chord to sit low without losing the ninth.
C add 9 is played in open position as 0 3 0 0: index finger on the A string at fret 3. The E, D and G strings ring open.
Tip — The hardest part is fretting the 3rd string at fret 3 without muting the adjacent open 2nd and 1st strings.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | open | — | E (3) |
| 3 (A) | 3 | 1 | C (1) |
| 2 (D) | open | — | D (9) |
| 1 (G) | open | — | G (5) |
C add 9 is played at the 9th fret as 10 10 10 9: middle finger on the E string at fret 10, ring finger on the A string at fret 10, pinky finger on the D string at fret 10 and index finger on the G string at fret 9.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 10 | 2 | D (9) |
| 3 (A) | 10 | 3 | G (5) |
| 2 (D) | 10 | 4 | C (1) |
| 1 (G) | 9 | 1 | E (3) |
C add 9 is written as C or Cadd9. The symbol 'C' alone can imply the add 9 in some contexts, but Cadd9 is explicit.
C add 9 contains the ninth (D) but no seventh, while C major 7 contains the seventh (B) but no ninth. C add 9 sounds more open and less jazzy.
Yes, the Cadd9/D inversion at fret 10 places D in the bass and sounds brighter. It works well for melodic passages.