AP Music Theory: Predominant Harmony Deep Dive 🎶

Hey there, future music maestro! Let's get you prepped and confident for the AP Music Theory exam. This study guide is your go-to resource for mastering predominant harmonies, especially those tricky seventh chords. Let's dive in!

Predominant Chords: The Bridge to the Dominant

Before we get fancy with seventh chords, let's nail down the basics. Predominant chords are like the 'setup' in a musical phrase, leading us smoothly to the dominant. Think of them as the 'getting ready' phase before the big 'ta-da!' of the dominant chord.

• Primary Predominants:

  • ii (supertonic): Minor chord built on the 2nd scale degree.
  • IV (subdominant): Major chord built on the 4th scale degree.

• Function: Predominant chords create a sense of anticipation, pushing the music towards the dominant (V). They expand the basic T-D-T (Tonic-Dominant-Tonic) progression to T-PD-D-T (Tonic-Predominant-Dominant-Tonic), which is super common!

• Common Progressions: I-ii-V-I and I-IV-V-I are your bread and butter. You've heard these a million times, whether you know it or not!

Remember the circle of fifths? Moving down it takes you from I to IV, which is why IV is a natural choice after the tonic. It's like a musical GPS guiding you through the harmony.

• Why IV First? It's a perfect fifth below the tonic, making it a smooth transition. Plus, you often keep a common tone between I and IV, which helps maintain a sense of connection. For example, in F Major, the I chord (F-A-C) and the IV chord (Bb-D-F) share the note F.

• Inversions: While root position is common, you'll also see the subdominant in first inversion (iv6) in minor keys. This is often to create a smoother bass line.

*Caption: Example of a iv6 chord in a minor key. Notice how the bass note is not the root of the chord.* 

The Supertonic Triad (ii or iio)

• Spice it Up: The ii chord is like the IV's cool cousin, adding a bit more harmonic flavor. It's a weaker substitute for IV but often follows it to expand the predominant section.

• Inversions: Usually in first inversion (ii6 or iio6). This puts the subdominant in the bass, emphasizing its function. Doubling the third in ii6 and iio6 also intensifies the subdominant feel.

Voice Leading from Predominant to V7

• Smooth Transitions: Use contrary motion and keep common tones whenever possible. The chordal seventh in the V7 needs to be prepared by a common tone.

Using Seventh Chords in the Predominant Section

Now, for the fun part! Seventh chords add a richer, more complex sound to the predominant section. Think of them as the 'deluxe' version of the triads.

Supertonic Seventh Chords (ii7 or iio7)

• Common Forms: Typically found in root position (ii7) or first inversion (ii 6/5). First inversion is favored for a stronger predominant feel because it puts the subdominant in the bass.

• Root Position Power: ii7 in root position is a strong predominant harmony, especially leading to a V7. - Other Inversions: The ii 4/2 chord can be a pedal tone in the tonic area (I-ii 4/2-I) or a predominant chord (I-ii 4/2-V 6/5-I). Context is key!

*Caption: Examples of ii7 chords in major and minor keys. Note the four notes in each chord.* 

Subdominant Seventh Chords (IV7 or iv7)

• Rare but Real: Not as common as ii7, but they do appear, especially in minor keys. Usually in root position if they are present.

Caption: Example of a iv7 chord in a minor key. Note the four notes in the chord.

• Root Position: It's okay to remove the fifth in seventh chords in root position. Double the third for a stronger subdominant sound. Remember that the third of a ii7 chord is the fourth scale degree.

• Resolve Down: Always resolve the chordal seventh down, except in cadential 6/4 chords (more on that later!). For ii7 chords, that means resolving the tonic down to the leading tone. This creates a lovely stepwise motion.

• High-Priority Topics: Predominant triads and seventh chords, voice leading rules, and recognizing common progressions.

• Common Question Types:

  • Multiple-choice questions on identifying chord functions and inversions.
  • Free-response questions requiring you to harmonize a melody using predominant chords and proper voice leading.

• Time Management: Practice writing chord progressions quickly and efficiently. Familiarize yourself with common patterns.

• Common Pitfalls: Avoid parallel fifths and octaves, and always resolve tendency tones correctly.

Practice Question

Practice Questions

Multiple Choice Questions

1. In a major key, which of the following chords typically functions as a predominant chord? (A) I (B) iii (C) IV (D) V

2. A ii6 chord in C major contains which of the following notes? (A) D-F-A (B) D-F-A-C (C) F-A-D (D) F-A-C-E

3. In a minor key, what is the most common inversion of the supertonic chord in a predominant section? (A) Root position (B) First inversion (C) Second inversion (D) Third inversion

Free Response Question

Instructions: Harmonize the following melody in C Major using four-part harmony. Include at least one predominant chord and one seventh chord. Use proper voice leading.

Melody: G4 - A4 - G4 - F4 - E4 - D4 - C4

Possible Solution:

Scoring Breakdown:

• Chord Choices (5 points): 1 point for each correct chord choice (I, ii, V, IV, ii7, I). Deduct 0.5 points for each incorrect chord.
• Voice Leading (5 points): 1 point for each measure with correct voice leading (no parallel 5ths/octaves, correct resolution of tendency tones). Deduct 0.5 points for each voice leading error.
• Seventh Chord (2 points): 2 points for including a seventh chord correctly (ii7 in this case), deduct 2 points if not included.
• Predominant Chord (2 points): 2 points for including a predominant chord correctly (ii and IV in this case), deduct 2 points if not included.

Short Answer Question

1. Explain the difference in function between a ii chord and a IV chord in a predominant section.

   • The IV chord is a stronger predominant chord, often used as the first predominant chord in a progression. The ii chord is a weaker substitute, often used after the IV chord to expand the predominant section. Both lead to the dominant chord (V).

2. What is the most important rule to remember when resolving the chordal seventh in a ii7 chord?

   • The chordal seventh in a ii7 chord should resolve down by step. This creates a smooth transition to the dominant chord.

Alright, you've got this! Keep practicing, and you'll be rocking the AP Music Theory exam in no time. Remember to breathe, stay calm, and trust your ears. You're going to do great! 🚀