AP Music Theory Unit 4: Principles of Harmony, Functions, and Phrase Structure

SATB

An acronym for Soprano, Alto, Tenor, Bass; a standard vocal arrangement in four-part harmony.

Voice Leading

The practice of arranging voices to create smooth and logical progressions between chords.

Closed Position

A literary arrangement where upper three voices are close together (within an octave).

Open Position

An arrangement of voices where the upper voices are spread out across more than an octave.

Parallel Motion

When two voices move in the same direction by the same interval.

Contrary Motion

When two voices move in opposite directions, promoting independence between voices.

Oblique Motion

One voice remains static while the other moves, creating motion with a common tone.

Forbidden Parallels

Musical errors involving the direct movement from one perfect interval to another in the same voices.

Voice Crossing

When a lower voice sings a pitch higher than an upper voice's current pitch.

Voice Overlapping

Occurs when a voice moves to a pitch that crosses the previous pitch of an adjacent voice.

Melodic Errors

Mistakes such as large leaps or leaps by dissonant intervals within a single voice line.

Functional Harmony

Chords that have specific roles or functions in music, typically moving between Tonic, Predominant, and Dominant.

Harmonic Progression

The movement of chords in a sequence, often following Tonic to Predominant to Dominant.

Cadence

A musical phrase's endpoint or conclusion, often identified by the last two chords.

Perfect Authentic Cadence (PAC)

A cadence where both chords are in root position and the soprano ends on the tonic.

Half Cadence (HC)

A cadence that ends on the Dominant chord, creating a feeling of unresolved tension.

Plagal Cadence (PC)

A cadence represented by the IV to I progression, often recognized as the 'Amen' cadence.

Deceptive Cadence (DC)

A cadence that moves from the Dominant to the submediant, surprising the listener.

Root Position Triads

Chords built with the root note as the lowest pitch.

First Inversion Triads

Chords where the third of the triad is the lowest note, often the nominal position in tonal harmony.

Second Inversion Triads

Chords where the fifth of the triad becomes the lowest note, typically functioning as passing chords.

Doubling Rules

Guidelines determining which note of a chord should be doubled in part-writing.

Tendency Tone

A note that leads strongly to another note, such as the leading tone resolving to the tonic.

Cadential 6-4 Chord

A decoration of the dominant chord that resolves to the tonic.

Harmonic Rhythm

The rate at which chords change in a piece of music, typically accelerating towards a cadence.

Agogic Accent

Aural emphasis derived from longer notes that suggest a change of harmony.

Leading Tone

The scale degree that leads to the tonic, typically resolving upward by step.

Common Practice Period

The era in Western classical music roughly from 1600 to 1900, defined by specific harmonic rules.

Soprano Range

Middle C to High G (C4 to G5), the highest voice in SATB.

Alto Range

Low G to High D (G3 to D5), the second highest voice in SATB.

Tenor Range

Bass C to High G (C3 to G4), the third voice in SATB.

Bass Range

Low E to Middle C (E2 to C4), the lowest voice in SATB.

Chord Functions

The roles that chords play in harmonic progressions, such as Tonic, Predominant, and Dominant.

Circle of Fifths Progression

A harmonic progression characterized by root movements descending by fifths or ascending by fourths.

Retrogression

Moving backwards functionally in a harmonic progression, typically avoided.

Voice Leading FRQs

Free Response Questions on the AP exam that require careful application of voice leading rules.

Harmonic Stability

The characteristic of a chord that establishes a strong tonal center, often related to the Tonic.

Diminished Triads

Triads built on a minor third and a diminished fifth, often used in a specific functional context.

AP Music Theory

An advanced placement course and exam in high school that covers the fundamentals of music theory.

Melodic Contour

The shape or outline of a melody as it moves through pitches.

Functional Bass Note

A bass note that plays a significant role in establishing the harmonic function of a chord.

Vertical Chords

Chords created when harmonies are stacked simultaneously in a specific arrangement.

Pitch Range Restrictions

Historical guidelines that delineate the acceptable ranges for different vocal parts.

Triadic Inversion

The rearrangement of a triad in different positions, affecting the bass note and sound.

Soprano Melody

The primary melodic line composed for the soprano voice, fundamental in part-writing.

Cadence Identification

The process of analyzing the final chords of a musical phrase to determine its closure type.

Authorization of Voice Parts

The rules governing how voices can interact and move in relation to each other.

Chord Qualities

The specific character or nature of a chord, dictated by its intervals.