The sus chord as a “dominant without a tritone”
A 7sus4 (G7sus4 = G C D F) replaces the third B with the fourth C. The tritone B–F is missing, so the dominant tension is suspended: the chord can resolve to C, stay still as a modal color, or move elsewhere. The main forms:
| Chord | Notes | Hybrid equivalent |
|---|---|---|
| G7sus4 | G C D F | — |
| G9sus4 | G C D F A | F/G, Dm7/G |
| G13sus4 | G C D F A E | roughly Fmaj7/G (G F A C E) |
| Gsus4(b9) | G C D F Ab | suspended Phrygian, Ab/G = “Phrygian chord” |
In modern jazz (since the 1960s) and contemporary pop, F/G and Dm7/G are the most common way of writing a “soft” dominant.
Maiden Voyage: the model
Maiden Voyage by Herbie Hancock (album of the same name, 1965) has a 32-bar AABA form with only one chord every 4 bars, all hybrid/sus:
| Section | Chords | Readings |
|---|---|---|
| A | Am7/D – Cm7/F | D9sus4 (D11), F9sus4 (F11) |
| A | Am7/D – Cm7/F | same |
| B | Bbm7/Eb – Dbm9 (also read as C#m13 or Abm7/Db) | Eb11, then minor |
| A | Am7/D – Cm7/F | same |
None of the chords resolves: each one is a mode (D Mixolydian sus, F Mixolydian sus, Eb Mixolydian sus, Db/C# Dorian). The piece moves from one mode to another: it is an example of polymodal modal jazz (several modes in succession, with no common key).
Polymodality: two meanings
- In succession (modal jazz): each chord or section has its own mode and center (Maiden Voyage, many pieces by Wayne Shorter and Chick Corea).
- Simultaneous on the same center (Bartók): two different modes on the same tonic played together. Bartók called “polymodal chromaticism” the union of, for example, C Lydian (C D E F# G A B) and C Phrygian (C Db Eb F G Ab Bb): together they contain all 12 notes, but each layer remains modal.
How to choose the scale over a sus chord
| Chord | Scale | Notes |
|---|---|---|
| G7sus4 / F/G | G Mixolydian | the 3 (B) may appear as a passing tone |
| G9sus4 without resolution | G Mixolydian or G Dorian | Dorian for a darker color |
| Gsus4(b9) | G Phrygian or Phrygian dominant | “Spanish” or dark modal color |
| Dm7/G (ii over the bass of the V) | G Mixolydian | the “ii–V in one chord” reading |
Sus in pop and electronic music
- Sus2 and sus4 as resting chords: Cadd9 and Csus2 in the pads of Coldplay and 2000–2020 pop.
- Joni Mitchell built many songs on open tunings and sus chords without a third: major/minor ambiguity.
- EDM and future bass: sus4 → major chords (Gsus4 → G) for emotional “drops.”
Producer exercise
- Reproduce the form of Maiden Voyage at 120 BPM in 4/4 with a straight groove: Am7/D (4 bars) – Cm7/F (4 bars), ×2; Bbm7/Eb (4) – Abm7/Db (4); the A section again.
- Piano or Rhodes: repeated syncopated rhythm (chord on 1 and on the “and” of 2).
- Improvise with the mode of each chord: D Mixolydian, F Mixolydian, Eb Mixolydian, Db Dorian. Hear how the light changes without cadences.
Related topics
Sus, add, slash, and hybrid chords, advanced quartal harmony (So What), hybrid chords and polychords, modal harmony for each mode, chord-scale theory.