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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
    4. Minor ninth flat fifth

    C Minor ninth flat fifth

    Minor ninth flat fifth (1–♭3–♭5–♭7–9); half-diminished color with added ninth.

    diminishedm9♭5

    Similar chords

    Guitar diagrams

    Piano voicings

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

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

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

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

    Practice the minor ninth flat fifth chord

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    Sheet music

    Practice the minor ninth flat fifth chord

    Open the app and start your daily workout!

    Learn music theory with sonid

    Available on Android and iOS

    The minor ninth flat fifth chord extends the half-diminished frame with a ninth (1-♭3-♭5-♭7-9). It keeps the searching quality of m7♭5 while the ninth adds width and a more modern jazz color—common as ø9 on ii in minor and in contemporary voicing studies.

    Construction

    Start from m7♭5 and add 9. In Cm9♭5, include D as the ninth.

    Usage

    iiø9–V progressions, altered pre-dominant colors, and linear improvisation targets.

    Examples

    • Minor-key jazz standards with rich ii chords
    • Modern arranging on half-diminished harmony
    • Voice-leading exercises emphasizing 9 as a melody tone

    Play

    Prioritize ♭3 and ♭7 guide tones; place the ninth where it sings without clashing the bass.

    Ear-training cues

    Half-diminished core with a bright ninth above.

    C dim
    C m7♭5
    C Chromatic
    C Composite blues
    C Dorian sharp four
    C Locrian ♯2
    C Messiaen's mode 3
    IntervalsemitonesNote
    0C
    2D
    3E♭
    6G♭
    10B♭
    Perfect unison
    Major second
    Minor third
    Diminished fifth
    Minor seventh