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    YoutubeMusic Theory Video SeriesA step-by-step guide to music theory fundamentals. These 60-second videos provide a clear, structured path to understanding how music works, optimized for a full-screen learning experience.YoutubeMusic Theory ShortsMaster music theory concepts in 60 seconds or less. Quick, vertical videos designed to give you essential theory knowledge in a fast-paced, mobile-friendly format.
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    1. Home
    2. Chord Library
    3. C sharp
    4. Minor ninth

    C sharp Minor ninth

    Minor ninth (1–♭3–5–♭7–9); minor seventh plus major ninth extension.

    minorm9-9

    Guitar diagrams

    Piano voicings

    Which intervals and notes are in the C sharp Minor ninth chord?

    Intervals from the root that spell this chord and its chord tones.

    To which mode does C sharp Minor ninth belong?

    Parent scales and degrees where this chord appears as a diatonic sonority.

    Which scales can you play on the C sharp Minor ninth chord?

    Scales that contain this chord’s notes and usually fit over it.

    Practice the minor ninth chord

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    Sheet music

    Practice the minor ninth chord

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    Learn music theory with sonid

    Available on Android and iOS

    The minor9 chord extends m7 with a major ninth: 1-♭3-5-♭7-9. It preserves minor-seventh depth while adding upper-register openness, making it one of the most important modern minor colors in jazz, neo-soul, R&B, and cinematic harmony.

    Construction

    Start from m7 and add the ninth. In Cm9, a common tone set is C-E♭-G-B♭-D. Real voicings often omit root or fifth, but the ninth should remain clearly identifiable.

    Sound Character

    Minor9 sounds warm, deep, and spacious. Compared with plain m7, it feels more vocal and "floating," especially when 9 is placed high and guide tones stay clear.

    Usage

    Core uses include ii9 chords in ii-V-I, i9 tonic color in modal minor, and long pads where harmony should stay minor but not closed or darkly compressed.

    Examples

    • ii9-V13-Imaj9 in jazz standards
    • Neo-soul and R&B keyboard voicings on i9
    • Pop/film textures replacing m7 with m9 for extra width

    Play

    Prioritize ♭3 and ♭7, place 9 in upper voices, and thin dense low stacks. Rootless shells plus 9 are often clearer than full close-position grips.

    Harmonic behavior

    Minor9 is flexible: it can act as functional pre-dominant (ii9), stable tonic extension (i9), or modal color chord. Small movements of 9 to ♭9 or 1 create immediate contrast.

    Ear-training cues

    Hear the m7 core with a bright top ninth. Alternate m7 and m9 to internalize the added openness quickly.

    NameAliasesDifficulty
    C sharp Dorian-Beginner
    C sharp MinoraeolianBeginner
    C sharp Chromatic-Easy
    C sharp Dorian sharp fourukrainian dorian, romanian minor, altered dorianEasy
    C sharp Bebop minor-Expert
    -Expert
    -Guru
    -Guru
    C sharp Minor bebop
    C sharp Composite blues
    C sharp Messiaen's mode 3
    IntervalsemitonesNote
    Perfect unison0C♯
    Minor third3E
    Perfect fifth7G♯
    Minor seventh10B
    Major ninth14D♯
    NameAliasesDifficulty
    C sharp Minorm, min, -Beginner
    C sharp Minor seventhm7, min7, mi7, -7Beginner
    C sharp Fifth5Beginner
    C sharp Suspended secondsus2Beginner
    C sharp Minor add ninthmadd9Easy

    DegreeTriadSeventhExtendedScale
    I
    II
    III
    IV
    V

    VI
    C♯
    m
    C♯
    m7
    C♯
    m9
    C♯
    m11
    C♯
    madd9
    C sharp Minor
    VII
    C♯
    m7♭5
    C sharp Locrian
    C♯
    M
    C♯
    maj7
    C♯
    maj13
    C♯
    maj9
    C sharp Major
    C♯
    m
    C♯
    m7
    C♯
    m9
    C♯
    m11
    C♯
    m13
    C♯
    m69
    C sharp Dorian
    C♯
    m
    C♯
    m7
    C♯
    m
    C sharp Phrygian
    C♯
    M
    C♯
    maj7
    C♯
    M13♯11
    C♯
    maj9♯11
    C sharp Lydian
    C♯
    M
    C♯
    7
    C♯
    13
    C♯
    9
    C♯
    7no5
    C sharp Mixolydian