Ninth chord
| Component intervals from root | |
|---|---|
| minor ninth | |
| minor seventh | |
| perfect fifth | |
| major third | |
| root | |
| Tuning | |
| 8:10:12:14:17 | |
|
Forte no. / |
|
| 5-31 / |
| Component intervals from root | |
|---|---|
| major ninth | |
| minor seventh | |
| perfect fifth | |
| minor third | |
| root | |
| Tuning | |
| 20:24:30:36:45 | |
|
Forte no. / |
|
| 5-27 / |
| Component intervals from root | |
|---|---|
| major ninth | |
| major seventh | |
| perfect fifth | |
| major third | |
| root | |
| Tuning | |
| 8:10:12:15:18 | |
|
Forte no. / |
|
| 5-27 / |
In music theory, a ninth chord is a chord that encompasses the interval of a ninth when arranged in close position with the root in the bass.
There is a difference between a major ninth chord and a dominant ninth chord. A dominant ninth is a dominant chord (and minor seventh) with a ninth. A major ninth chord (e.g., Cmaj9), as an extended chord, adds the major seventh along with the ninth to the major triad. Thus, a Cmaj9 consists of C E G B and D 
play . When the symbol "9" is not preceded by the word "major" or "maj" (e.g., C9), the chord is a dominant ninth. That is, the implied seventh chord is a dominant seventh, i.e. a major triad plus the minor seventh, to which the ninth is added: e.g., a C9 consists of C, E, G, B♭ and D play . C dominant ninth (C9) would usually be expected to resolve to an F major chord (the implied key, C being the dominant of F). The ninth is commonly chromatically altered by half-step either up or down to create more tension and dissonance. Fétis tuned the chord 4:5:6:7:9.
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Wikipedia