Definition
The secondary (or non-dominant) sevenths are seventh chords built on degrees other than the V: in C major Imaj7 (C–E–G–B), ii7 (D–F–A–C), iii7 (E–G–B–D), IVmaj7 (F–A–C–E), vi7 (A–C–E–G). In the Classical style their seventh is a dissonance to be prepared and resolved; in jazz and pop it becomes instead a stable color.
The Classical treatment of the seventh
- Preparation: the note that will become the seventh is present in the same voice in the preceding chord as a consonance (for example the C in I, which stays and becomes the seventh of ii7).
- Dissonance: the seventh sounds on the strong beat or at the arrival of the chord.
- Resolution: it falls by step onto the next chord (C → B in the V).
It is the same pattern as the suspension: for this reason in Baroque progressions sevenths link together like a chain of suspensions.
The individual chords
| Chord | Function | Typical use | Resolution of the seventh |
|---|---|---|---|
| ii7 (and ii6/5, F in the bass) | predominant | ii6/5 – V – I, the most frequent | C → B |
| IVmaj7 | predominant | IV7 – V, in progressions by fifths | E → D |
| vi7 | link toward the ii | vi7 – ii7 – V7 – I | G → F |
| Imaj7 | dissonant tonic, rarely at the end | Imaj7 – IVmaj7 in progression | B → A |
| iii7 | link toward the vi | iii7 – vi7 | D → C |
| viiø7 | dominant | see dedicated entry | A → G |
Progressions of sevenths
A chain of descending fifths with all diatonic sevenths: Imaj7 – IVmaj7 – viiø7 – iii7 – vi7 – ii7 – V7 – I. In Classical four-voice writing, complete and incomplete chords (without fifth) alternate to avoid parallels: each seventh is prepared as a common tone and falls onto the next chord, where it becomes the third.
Practical rules
- In the Classical style, the ii6/5 is the safest secondary seventh: the F in the bass rises to G, the C (seventh) falls to B.
- Prepare the seventh whenever you can; alternatively let it enter by step as a passing note.
- In jazz and pop the seventh needs neither preparation nor resolution: Cmaj7 and Fmaj7 can last for whole bars.
- The major seventh (Imaj7, IVmaj7) is more dissonant than the minor (ii7, vi7): in Classical style it must be handled with more care.
Common mistakes
- Making the seventh rise in Classical voice leading.
- Ending a Classical piece on an Imaj7: in the 18th-century tonal style it is not a stable tonic.
- Doubling the seventh.
Examples
- Bach, Prelude in C major (Well-Tempered Clavier, I): in the second bar a Dm7 appears with the C in the bass (ii4/2), prepared by the preceding tonic; the C then falls to B in the G7/B of the next bar.
- Corelli and Vivaldi: descending-fifth progressions with chains of sevenths in the trio sonatas and concertos.
- “Autumn Leaves”: Am7 – D7 – Gmaj7 – Cmaj7 – F#m7(b5) – B7 – Em is the chain of diatonic sevenths by fifths.
- “Fly Me to the Moon”: Am7 – Dm7 – G7 – Cmaj7 – Fmaj7 – Bm7(b5) – E7 – Am.
How to use it in composition
- For a Baroque progression, write a chain of descending fifths with prepared sevenths: the result is a continuous, “inevitable” drive.
- In pop, adding the seventh to the ii, IV, and vi degrees softens the sound without changing the function.
- Use Imaj7 and IVmaj7 for dreamy atmospheres (city pop, neo-soul, bossa nova).
Exercise
- Write in G major in four voices: I – ii6/5 – V7 – I, preparing the seventh of the ii.
- Write the complete chain of sevenths by fifths in F major, alternating complete and incomplete chords.
- Reharmonize an I – vi – ii – V loop of a song using only sevenths and listen to the change in color.
Connections
The qualities of seventh chords; Seventh chords; Harmonic sequences and progression by fifths; Suspensions; The jazz ii–V–I; Neo-soul harmony.