Lesson 42 · All 12 keys

Minor 9th Chord Trainer

Learn how a Minor 9th chord is built one semitone-count at a time — a minor 7th chord (Lesson 15) with a 9th stacked on top — then put it to work with three MIDI exercises: playing all 12 minor 9th chords around the circle of fourths, and 5 jazz plus 5 gospel chord progressions that show off its color, in every key.

How a Minor 9th chord is built

A Minor 9th chord — written m9 (e.g. Cm9) — is a 5-note chord: a minor 7th chord (Lesson 15) with a 9th stacked on top. Every m9 chord — in any of the 12 keys — is built the exact same way, by counting semitones to the right from a root note:

  1. The starting note — this note names the chord.
  2. Count 3 semitones up from the root — the minor 3rd.
  3. Count 4 more semitones up from the 3rd (7 semitones from the root) — the perfect 5th.
  4. Count 3 more semitones up from the 5th (10 semitones from the root) — the minor 7th, the same 7th a plain minor 7th chord uses.
  5. Count 4 more semitones up from the 7th (14 semitones from the root — an octave plus a major 2nd) — the 9th, stacked on top of a complete minor 7th chord.
Example — Cm9: start on C, count 3 semitones right to reach E♭, count 4 semitones more to reach G, count 3 semitones more to reach B♭, count 4 semitones more to reach D. C‑E♭‑G‑B♭‑D is the Cm9 chord.
A minor 9th chord still contains the full minor 7th chord underneath (root, ♭3rd, 5th, ♭7th) — it just adds a smooth 9th on top. It is one of the most common ii-chord voicings in jazz, and is built the exact same way in every key.

Try it: pick a root and build the chord step by step

Step 1 of 5
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Chord toneNoteSemitones from rootMIDI #

All 12 minor 9th chords at a glance

ChordRootMinor 3rdPerfect 5thMinor 7th9th

This MIDI exercise plays all 12 minor 9th chords, one after another, moving around the circle of fourths — each chord's root sits a perfect 4th (5 semitones) above the last one: C → F → B♭ → E♭ → A♭ → D♭ → G♭/F♯ → B → E → A → D → G → back to C. Every chord is played as a full 5-note Minor 9th chord (root, minor 3rd, perfect 5th, minor 7th, 9th together).

Chord 1 of 12
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The 12 chords, in circle-of-fourths order

#ChordRootMinor 3rdPerfect 5thMinor 7th9th

Five jazz chord progressions built around the Minor 9th chord. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes

Five gospel chord progressions built around the Minor 9th chord. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes