Harmonic Function and Voice Leading: every key term you need (+ practice quiz)
34 flashcard terms for AP Music Theory Unit 4, written to match the course framework. Study them here, then drill them as interactive flashcards, or test yourself with the 19-question quiz — free, no account needed.
The art of connecting chords so each of the four voices moves smoothly, preserving independence while forming correct harmonies.
SATB Texture
Four-voice chorale texture: soprano, alto, tenor, bass; soprano and alto share the treble staff, tenor and bass the bass staff.
Vocal Ranges
Approximate SATB ranges: soprano C4–G5, alto G3–D5, tenor C3–G4, bass E2–C4; exam writing must stay within them.
Voice Crossing
An error in which a lower voice moves above a higher voice (e.g., alto above soprano) within a chord.
Voice Overlap
An error in which a voice moves past the previous position of an adjacent voice between chords.
Parallel Fifths
Two voices a perfect 5th apart moving to another perfect 5th in the same direction; forbidden because it destroys voice independence.
Parallel Octaves
Two voices an octave (or unison) apart moving to another octave in parallel; forbidden for the same reason as parallel 5ths.
Contrary Motion
Two voices moving in opposite directions; the safest motion for avoiding parallels.
Oblique Motion
One voice holds a common tone while another moves.
Similar Motion
Two voices moving the same direction by different intervals; acceptable except in specific outer-voice situations.
Direct (Hidden) Fifths/Octaves
Outer voices approaching a perfect 5th or octave in similar motion with a leap in the soprano; avoided in strict style.
Tendency-Tone Resolution
The leading tone (7̂) resolves up to 1̂ (especially in an outer voice); the chordal 7th resolves down by step.
Common-Tone Retention
Keeping a shared pitch in the same voice between chords, the smoothest connection between root-position chords a 4th or 5th apart.
Doubling Rules
Root position: double the root. First inversion: double soprano note or any non-tendency tone. 6/4 chords: double the bass (the fifth). Never double 7̂ or a chordal 7th.
Harmonic Function
Chords grouped by role: tonic (I, vi), predominant/subdominant (IV, ii), dominant (V, vii°); phrases flow T → PD → D → T.
Tonic Function
Chords of stability and arrival: I (and i); vi can substitute in progressions.
Predominant Function
Chords that prepare the dominant: IV and ii (ii6 favored in four-part writing).
Dominant Function
Chords demanding resolution to tonic: V, V7, and vii°6, all containing the leading tone.
Standard order tonic → predominant → dominant → tonic; retrogressions like V–IV are avoided in common practice.
Non-Chord Tone (NCT)
A melody note outside the sounding harmony, classified by how it is approached and left.
Passing Tone
NCT approached and left by step in the same direction, filling the gap between two chord tones.
Neighbor Tone
NCT approached by step and left by step in the opposite direction, returning to the same chord tone.
Suspension
Accented NCT held over from the previous chord, then resolved down by step; labeled by intervals (4–3, 7–6, 9–8, and bass 2–3).
Retardation
Like a suspension but resolving up by step, most often 7–8 at a cadence.
Appoggiatura
Accented NCT approached by leap and resolved by step, usually in the opposite direction.
Escape Tone
NCT approached by step and left by leap in the opposite direction.
Anticipation
Unaccented NCT that arrives early, sounding a note of the next chord before the chord changes.
Pedal Point
A sustained bass pitch (usually tonic or dominant) held while harmonies change above it.
Suspension Figures
The standard suspensions: 4–3, 7–6, 9–8 in upper voices, 2–3 in the bass; the dissonance falls on the strong beat.
Texture Types
Monophony (one line), homophony (melody with accompaniment/chords), polyphony (independent simultaneous lines), heterophony (simultaneous variants of one line).
Melodic Writing Norms
Prefer steps; leaps larger than a 4th are followed by a step in the opposite direction; avoid augmented intervals like the A2.
Chordal Skip (Arpeggiation)
Melodic leap between two tones of the same chord; not an NCT because both notes are chord members.
Cadential Approach
At cadences the leading tone in the soprano must rise to tonic; inner-voice leading tones may drop to 5̂ for a full triad.
Cross Relation
A chromatic contradiction — the same letter name appearing natural in one voice and altered in another voice in adjacent chords; avoided in strict style.