Harmonia.
Level 1 · Lesson 7

Tonicisation

Secondary dominants, neighbouring keys and chains — making a chord temporarily tonic.

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Pause Culture · Tonicization
Ludwig van Beethoven (1770–1827)

At the opening of his First Symphony, Beethoven does something scandalous for the time: instead of starting with a C major chord, he opens with a dominant seventh chord that resolv…

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À retenir : Tonicization is a harmonic optical illusion: a new king is installed, but immediately dethroned.

The Principle of Tonicization

Tonicization means treating a chord — just for an instant — as a temporary tonic, by preceding it with its own dominant (and optionally its subdominant). It is another form of borrowing: instead of replacing a chord with another, we prepare it using the chords of its own key.

Simple definition: any chord in a progression can be treated as a temporary tonic. It can therefore be prepared with its own dominant — called a secondary dominant.

Tonicization differs from modulation: we never leave the main key. The secondary dominant is a passing color — after it, we naturally return to the progression.

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Can be tonicized

Any diatonic chord except the main tonic and diminished chords.

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Cannot be tonicized

The main tonic (already the tonic) and diminished chords (too unstable to assume the tonic function).

Fundamental example: tonicizing G (V of C)

In C major, G7 is the dominant. We can reinforce its arrival by preceding it with its own dominant — D7. Instead of C – G7 – C, we write C – D7 – G7 – C.

Progression: C – D7 – G7 – C (V/V – V – I)
C → D7 → G7 → C
D7 contains F# (F-sharp) — the artificial leading tone of G. F# rises a half step to G. Without F#, G would lack this reinforcement.
Note: tonicization is not modulation. After D7–G7, we return to C — the tonal center has never changed. D7 is a passing color, not a new center.

Practical shortcut

In practice, we can bypass the subdominant and move directly to the secondary dominant. Instead of SD/X → V/X → X, we simply write V/X → X. V/V can even replace a subdominant chord in the progression.

Choose the correct inversion

For each progression, choose the inversion that ensures the best voice leading.

Renversementstonicisationrenversement

Dans C → A7 → Dm → G7 → C, quel renversement de A7 améliore la conduite de voix ?

C →A7 ?→ Dm → G7 → C
A7
État fondamental — La à la basse
A7/C#
1er renversement — Do# à la basse
A7/G
3e renversement — Sol à la basse
Renversementstonicisation en chaînerenversement

Dans C → D7 → G7 → C (V/V), quel renversement de D7 crée une basse plus intéressante ?

C →D7 ?→ G7 → C
D7
État fondamental — Ré à la basse
D7/F#
1er renversement — Fa# à la basse
D7/C
3e renversement — Do à la basse