AP Music Theory: Tonicization and Modulation - Your Last-Minute Guide 🚀

Hey there, future music maestro! Feeling the pre-exam jitters? Don't worry, we've got this. Let's dive into tonicization and modulation, the final frontier in adding color and excitement to music. Think of it as musical travel – we're going to visit some new keys, but we'll always find our way back home. Let's get started!

Tonicization: A Quick Trip to a New Key 🧳

• Tonicization is like a mini-vacation for your music. It's a brief visit to another key, where we borrow some of its chords and notes to add flavor. The key we're visiting is called the secondary key, and its tonic is the temporary tonic.

  • Think of it as a quick detour – we're not moving permanently, just experiencing a new sound for a bit.

• For example, in C major, tonicizing G major means using chords and progressions typical of G major (like G major chord or I-V-vi-IV in G) before returning to C major.

• Secondary keys are usually closely related keys to the primary key. These keys share many pitches and chord progressions, making transitions smooth and natural.

• Think of them as neighbors on the musical map – they're close by and share a lot in common.

• Here are the types of closely related keys:

  1. Relative Keys: Share the same key signature but have different tonics (e.g., C major and A minor).
  2. Dominant and Subdominant Keys: A perfect fifth apart (e.g., G is the dominant of C, F is the subdominant of C).
  3. Tonic and Dominant Keys: A perfect fourth apart (e.g., F is the dominant of Bb, Bb is the tonic of F).

• Circle of Fifths: A handy tool! Keys next to each other on the circle are closely related. For example, from A major:

  • Relative minor: F# minor
  • Adjacent major keys: D major and E major
  • Relative minors of adjacent major keys: B minor and C# minor

  

  • Image via Neel Modi

• Quick Check: Closely related keys are usually just one accidental away from the original key. A Major (3 sharps), D Major (2 sharps), and E Major (4 sharps) are good examples.

Identifying Tonicizations: Detective Work 🕵️‍♀️

• Look for accidentals from closely related keys. Especially look for accidentals (not leading tone in minor) that resolve upward by step (leading tone relationship) – likely a temporary tonic.

• Once you find the temporary tonic, the chord before it is likely a dominant function chord (V or vii° of the secondary key).

• Example: In D major, a G# appears, leading to A. This suggests a tonicization to A major (closely related to D major).

  • The chord before A is G# B D, which is the V7 of A major. We notate this as V65/V.

  

  • Image via expandingthemusictheorycanon.com

• Notation: V65/V means "V 6/5 of V," a first inversion V7 chord in the temporary key of the dominant scale degree of the primary key.

Secondary Dominants: The VIPs of Tonicization👑

• The chord leading to the temporary tonic is usually a dominant chord because its leading tone strongly resolves to the tonic, making the temporary tonic sound like a true tonic.

• These temporary dominant chords are called secondary dominants.

• Most Common: V/V (dominant of the dominant). In C major, the V/V is D major (V of G), which temporarily tonicizes G major before returning to C major.

• Secondary dominants can tonicize other chords:

  • V/ii: In C major, A major followed by D minor temporarily tonicizes D minor.
  • V/IV: In C major, resolves to the IV chord. (May be hard to distinguish from I-IV without context).

• Context is Key: Look for accidentals (like Bb in C major) or frequent use of the subdominant tone to identify V/IV.

Cadential Extension: Adding Drama 🎭

• Secondary dominants are often used around cadences, and can be extended to create longer chains of tonicization (cadential extension).

• Cadential Extension involves using multiple secondary dominants in succession, creating tension and release.

• Suffixes: Harmonic extensions after resolving to the dominant, often tonicizing other chords to prolong the section.

  • Example: V-I, then V/ii-ii, etc.
  • Can resolve back to the home key (ascending fourths) or modulate to a new key.
  • Involve chromaticizations to ensure the secondary dominant is a major triad or major-minor seventh chord.

• Prefixes: Similar to suffixes but appear before the final cadence, ending with a cadence in the home key.

  • Example: ii-V/IV-IV-V-I
  • Context is crucial: ii-I-IV-V-I obscures the secondary dominant function of the I chord.

Final Exam Focus 🎯

• High-Priority Topics: Tonicization, secondary dominants (especially V/V), and cadential extensions.
• Question Types: Expect to identify tonicizations, analyze secondary dominants, and understand how they function within a musical passage. You might need to notate them correctly using Roman numerals.
• Time Management: Quickly identify accidentals and leading tone relationships. Don't get bogged down on one section – move on if you're stuck and come back later. Remember to always look at the context.
• Common Pitfalls: Confusing tonicization with modulation (modulation is a more permanent change of key), misidentifying secondary dominants, and not contextualizing the music.

Practice Question

Practice Questions 📝

Multiple Choice Questions

1. In the key of G major, which of the following chords would be a secondary dominant of the dominant? a) C major b) D major c) A major d) E major

2. What is the relationship between the keys of A major and F# minor? a) Parallel keys b) Dominant and subdominant c) Relative keys d) Unrelated keys

3. Which of the following is the correct notation for a V7 chord in the key of D major that is functioning as a secondary dominant of the dominant? a) V7/IV b) V7/V c) V7/ii d) V7/vi

Free Response Question

Analyze the following excerpt, identifying the key, any tonicizations, and secondary dominants. Notate the chords using Roman numerals, including secondary dominant notation. (Assume standard 18th-century voice leading rules)

[Music Excerpt in C Major]
C: I  | G7  | C | Am | Dm | G7 | C
      |   |  |   | A7 | Dm | G7 | C

Scoring Breakdown:

• Key (1 point): Correctly identifying the primary key as C major.
• Tonicization (2 points): Identifying the tonicization to D minor in measure 2 and 3. * Secondary Dominant (2 points): Correctly labeling the A7 chord as V7/ii in measure 2. * Roman Numeral Analysis (3 points): Correctly notating all chords with Roman numerals, including the secondary dominant notation. (I, V7, I, vi, ii, V7, I, V7/ii, ii, V7, I)

Let's do this! You've got the knowledge and the tools – now go ace that exam! 🎉