Lesson 51 · All 12 keys

Dominant 9sus4 Chord Trainer

Learn how a Dominant 9sus4 chord is built one semitone-count at a time — a dominant 7sus4 chord (Lesson 29) with a 9th stacked on top — then put it to work with three MIDI exercises: playing all 12 dominant 9sus4 chords around the circle of fourths, and 5 jazz plus 5 gospel chord progressions that show off its color, in every key.

How a Dominant 9sus4 chord is built

A Dominant 9sus4 chord — written 9sus4 (e.g. C9sus4) — is a 5-note chord: a dominant 7sus4 chord (Lesson 29) with a 9th stacked on top. Every 9sus4 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 5 semitones up from the root — the perfect 4th, replacing the 3rd exactly like a sus4 chord (Lesson 28).
  3. Count 2 more semitones up from the 4th (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 dominant 7sus4 chord (Lesson 29) 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.
Example — C9sus4: start on C, count 5 semitones right to reach F, count 2 semitones more to reach G, count 3 semitones more to reach B♭, count 4 semitones more to reach D. C‑F‑G‑B♭‑D is the C9sus4 chord.
With no 3rd of any kind, a dominant 9sus4 chord is neither major nor minor — that "no 3rd" openness is exactly what makes it such a common gospel and R&B vamp chord, often sustained for whole phrases without ever resolving.

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 dominant 9sus4 chords at a glance

ChordRootPerfect 4thPerfect 5thMinor 7th9th

This MIDI exercise plays all 12 dominant 9sus4 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 Dominant 9sus4 chord (root, perfect 4th, perfect 5th, minor 7th, 9th together).

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

#ChordRootPerfect 4thPerfect 5thMinor 7th9th

Five jazz chord progressions built around the Dominant 9sus4 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 Dominant 9sus4 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