Modulation by Pivot Chord
Changing key smoothly — the pivot chord, cadential 6/4 and V7sus4.
In his 'Dissonance' quartets, Mozart uses pivot chords so subtle that musicians of the time believed them to be printing errors in the score. The transition from one key to another…
À retenir : Modulation is a journey: the pivot chord is the invisible gateway to a new world.
Logic of a modulation
Modulation is fundamentally different from borrowing or tonicization. It is no longer a mere play of colors — it is a genuine journey. When a composer modulates, the reference tonality changes. The harmonic center of gravity shifts durably.
Borrowing = a passing color (a foreign chord, immediately returning).
Tonicization = a momentary temporary tonic (a few chords, then back).
Modulation = a lasting journey — confirmed by a perfect cadence in the new center.
The three conditions for a true modulation
The departure tonality must fade — the new one can only establish itself once the old one has weakened.
A perfect cadence (V–I, both in root position) in the new tonality — this is the strong acoustic signal.
We remain in the new tonality long enough for the ear to adopt it as the new center. A single chord is not enough.
Closely related keys — the preferred destinations
The closer two keys are (sharing many notes), the smoother the modulation and the more abundant the pivots. Closely related keys are the natural destinations for modulation.
| Destination | Relation to C | Common notes | Ease |
|---|---|---|---|
| G major | Dominant (V) | 6/7 | Very easy |
| F major | Subdominant (IV) | 6/7 | Very easy |
| A minor | Relative minor (VI) | 7/7 | Natural |
| D minor | 2nd degree | 6/7 | Easy |
| E minor | 3rd degree | 6/7 | Easy |
| Eb major | Mediant (borrowed) | 2-3/7 | Difficult — rare pivot |
Choosing the right inversion
For each progression, choose the inversion that ensures the best voice leading.
Am est l'accord pivot (VI en C = II en G). Quel renversement d'Am facilite la transition vers D7 → G ?