#AP Music Theory: The Night Before Cram Session 🎶

Hey there, future music maestro! Feeling the pressure? Don't worry, we've got this. Let's turn those notes into a symphony of understanding. This guide is designed to be your go-to resource for a confident test day. Let's dive in!

#4.1: Harmony and Voice Leading I

#What is Voice Leading?

Voice leading is how individual voices move from chord to chord. Think of it as the choreography of your musical lines. It’s all about creating smooth, pleasing transitions. We're focusing on the Common Practice Period (CPP), roughly 1650-1900, where these rules were developed.

#Types of Motion

In four-part writing, voices move in four ways:

1. Parallel Motion: Voices move in the same direction by the same interval.
2. Similar Motion: Voices move in the same direction but by different intervals.
3. Oblique Motion: One voice stays put while the other moves.
4. Contrary Motion: Voices move in opposite directions.

#18th-Century Voice Leading Rules

These are the golden rules for smooth voice leading:

• Stepwise Motion: Voices should move mostly by step, avoiding big leaps.
• Common Tones: Keep common tones in the same voice when moving between chords.
• SATB Order: Maintain Soprano-Alto-Tenor-Bass order to avoid voice crossing.
• Avoid Parallel Fifths and Octaves: Don't move to a perfect fifth or octave from another perfect fifth or octave in parallel motion. This also applies to contrary motion and nonadjacent chords.

* **Melodic Intervals**: Use major and minor seconds, thirds, perfect fourths, and perfect fifths melodically. Avoid augmented, diminished intervals, and leaps larger than a perfect fifth. * **Leading Tone**: Resolve the leading tone in an outer voice (soprano or bass) up by step. * **Implied Chords**: Ensure soprano notes make harmonic sense with implied chords. * **Acceptable Progressions**: Use tonic, supertonic, subdominant, and dominant triads following harmonic progression norms. * **Repeated Harmonies**: Okay on strong beats, or weak beats at the beginning of a phrase. * **Bass Line**: Balance upward and downward motion with steps and leaps. Leaps are more common in the bass than in upper voices. * **Bass Leaps**: Use thirds, perfect fourths, fifths, sixths, and octaves. Octave leaps should change direction. Successive leaps can outline a triad. * **Repeated Bass Notes**: Okay on strong beats, or weak beats at the start of a phrase or as a suspension. * **Bass Rhythms**: Quarter notes are most common, but half notes to eighth notes are okay. * **Outer Voice Dissonances**: Avoid augmented and diminished intervals, especially tritones, between outer voices. Fourths, major, and minor sevenths and seconds are generally okay. * **Cross-Relations**: Avoid chromatic alterations between voices, especially in minor keys with raised sevenths.

#4.2: SATB Voice Leading

#SATB: The Core of Choral Music

SATB stands for Soprano, Alto, Tenor, and Bass. These are the four main vocal parts in choral music, arranged from highest to lowest. Think of them as the four main characters in your musical story.

#Voice Leading in SATB

Good voice leading in SATB creates a smooth and harmonically interesting texture. It’s about how these four voices interact and move together. We also use SATB to complete Roman numeral analysis, figuring out the diatonic chord and its inversion.

#Doubling Rules

Since triads have three notes and we're working with four voices, we need to double one note. Here's how to choose:

• Double the Root: Whenever voice leading allows, double the root of a triad.

* **Thirds and Fifths**: Double thirds and fifths if it results in good voice leading. * **Non-Tendency Tones**: Always double non-tendency tones (not the leading-tone or chordal seventh). * **Omitted Fifth**: If you omit the fifth in a root-position seventh chord, double the root. * **V7 to I**: Following a complete root position V7, the tonic triad may have three roots and a third (no fifth). * **6/4 Chords**: Always double the bass in 6/4 chords.

#4.3: Harmonic Progression, Functional Harmony, and Cadences

#Harmonic Progression

Diatonic chords follow predictable sequences called harmonic progressions. These sequences create structure and emotional impact. Think of it as the musical path that leads you home.

#Tonic and Dominant

The tonic is your home key—stable and resolving. Chords with a dominant function create tension and lead back to the tonic. The V and vii chords have dominant function, with V being the stronger of the two. Scale degree 5 wants to resolve to scale degree 1. ### Cadences: The Endings

Cadences are like musical punctuation marks. They provide different levels of resolution:

• Half Cadence (HC): Ends on a V chord. Feels unresolved, like a musical question.

  

• Deceptive Cadence (DC): V chord moves to a non-tonic chord (often vi/VI or IV/iv). Creates a surprise.

  

• Plagal Cadence (PC): Moves from IV/iv to I. A strong resolution, often called the "amen" cadence.

  

• Authentic Cadence (AC): V (or vii) resolves to I.

  • Perfect Authentic Cadence (PAC): Both V and I are in root position, and the soprano ends on scale degree 1. The strongest resolution.
  • Imperfect Authentic Cadence (IAC): Either V or I is inverted, or the soprano ends on a non-tonic pitch.

  

#4.4: Voice Leading with Seventh Chords

#Seventh Chord Rules

When writing with seventh chords, remember these key rules:

• Approach by Step or Common Tone: Chordal sevenths should be approached by step or common tone.

* **Resolve Downward**: Chordal sevenths should resolve down by step, unless suspended or in a I-V4/3-I6 progression. * **Omit the Fifth**: In a root position dominant seventh chord, you can omit the fifth and double the root.

#4.5: Voice Leading with Seventh Chords in Inversions

#Leading-Tone Seventh Chords

Leading-tone seventh chords (ⅶo7 and ⅶø7) have two main functions:

• Substitute for V or V7 as part of the dominant.
• Placed between tonic chords to prolong the tonic with stepwise voice leading.

#Final Exam Focus 🎯

Okay, you've made it! Here’s what to focus on for the exam:

• Voice Leading Rules: Pay extra attention to parallel fifths/octaves, leading tone resolution, and doubling rules.
• Cadences: Know the differences between PAC, IAC, HC, DC, and PC. Be able to identify them in a score.
• Seventh Chords: Understand how to approach and resolve chordal sevenths.
• SATB: Practice writing and analyzing four-part harmony.

#Exam Tips

• Time Management: Don't get stuck on one question. Move on and come back if needed.
• Read Carefully: Pay attention to all instructions and details.
• Practice, Practice, Practice: Do as many practice questions as possible.
• Stay Calm: Take deep breaths. You've got this!

#Practice Questions

Practice Question

#Multiple Choice Questions:

1. In four-part writing, which type of motion involves voices moving in the same direction by different intervals? a) Parallel motion b) Similar motion c) Oblique motion d) Contrary motion

2. Which of the following is NOT a common rule for 18th-century voice leading? a) Voices should move mostly by step. b) Common tones should be retained in the same voice. c) Parallel fifths and octaves are acceptable. d) The leading tone should resolve up by step.

3. A deceptive cadence typically involves which chord progression? a) V-I b) IV-I c) V-vi d) ii-V

#Short Answer Question:

Explain the difference between a Perfect Authentic Cadence (PAC) and an Imperfect Authentic Cadence (IAC). Be sure to include specific details about the chord positions and soprano voice in each.

#Free Response Question:

Given the following chord progression in C major: I - V6 - vi - IV - ii6 - V - I

1. Write out the four-part harmony (SATB) for the above progression, following the rules of 18th-century voice leading.
2. Identify the type of cadence at the end of the progression.
3. Explain any doubling you did for the triads in the progression and why you chose to double those notes.

FRQ Scoring Rubric

• (1 point) Correctly notating all chords in the given progression using proper SATB voice leading.
• (1 point) Correctly identifying the cadence as a Perfect Authentic Cadence (PAC).
• (1 point) Explaining the doubling of the roots in the I, vi, and IV triads, and the reason for choosing to double the root in each case.

You've got this! Go get 'em!