Minor ninth chords (m9) add a major ninth above a minor-seventh chord, producing a beautiful mellow sound used in deep house and ambient

Adding a ninth (major, minor, or diminished) above a seventh chord creates a ninth chord. Minor ninth chords (m9 = root + minor third + fifth + minor seventh + major ninth) have a particularly beautiful, rich, mellow quality. They are among the most expressive chord types in electronic music, used extensively in deep house, nu jazz, and ambient. The ninth gives the chord an added-note fullness that floats above the bass. The dominant minor ninth (flat 9 on a major-minor seventh chord) has a sharper, more dramatic character used in jazz and film music.

Examples

Am9: A C E G B. Dm9: D F A C E. In deep house: a 4-bar loop on Am9 with subtle filter movement is a complete musical statement.

Assessment

Build Cm9 and Em9. Describe how a minor ninth chord sounds different from a plain minor seventh chord. Name a context where you would use a dominant flat-9 instead.