Unit 5: Harmony and Voice Leading II - Functional Harmony

Functional Harmony

A grammatical logic in tonal music that governs the sequence of chords.

Phrase Model

A summary of functional harmony used in AP Music Theory.

Tonic (T)

The stability chord that serves as the home base, often represented by $I$ or $i$.

Predominant (PD)

The chord that prepares the dominant, typically $IV$ or $ii$.

Dominant (D)

The chord that creates tension, usually $V$ or $vii^ullet$.

Retrogression

Moving backward through chords in music, such as from Dominant back to Predominant.

Subdominant (IV)

A predominant chord that often leads to the dominant (V).

Voice Leading

The way in which individual musical lines or voices move from one chord to the next.

Supertonic ($ii$)

A predominant chord that prepares the dominant, considered a stronger predominant than IV.

Diminished Triad ($ii^ullet$)

The ii chord in minor keys, which is dissonant and often in first inversion.

Common Progression

A typical chord sequence: $I
ightarrow IV
ightarrow ii
ightarrow V
ightarrow I$.

Circle of Fifths Progression

A harmonic motion characterized by descending perfect fifths or ascending perfect fourths.

Six-Four Chord

A triad with the fifth in the bass, noted as $^6_4$, considered dissonant.

Cadential Six-Four ($cad^6_4$)

A six-four chord that functions as a dominant preparation.

Passing Six-Four

A six-four chord that connects root position to first inversion via stepwise motion.

Pedal Six-Four

A six-four chord where the bass note remains stationary while the upper voices move.

Arpeggiated Six-Four

A six-four chord where the bass arpeggiates while the harmony remains static.

Universal Rule for 6/4 Chords

Always double the bass in six-four chords and never double the root or third.

Metrical Placement

The rhythmic emphasis of a chord, whether on a strong or weak beat.

Common Mistake: Cadential 6/4 as Tonic

Mislabeling a $I^6_4 - V - I$ progression as Tonic - Dominant - Tonic.

Incorrect Doubling in 6/4 Chords

Mistakenly doubling the root instead of the bass in a second inversion triad.

Parallel Octaves/Fifths

Moving all voices in the same direction when transitioning from IV to V, which is avoided.

Flow of Harmony

The idea that progressions generally move forward from Predominant to Dominant to Tonic.

First Inversion ($ii^{ullet 6}$)

A condition where the third of the diminished ii chord is in the bass for stability.

Contrary Motion

A voice leading technique where upper voices move in the opposite direction to the bass.

Tension in Music

The concept that certain chords (like Dominant) create a need for resolution back to Tonic.

Preparation in Harmony

A function of the Predominant chords (ii and IV) that prepares the listener for the Dominant.