AP Music Theory Unit 6 Review: Embellishments, Motives, and Melodic Devices

Passing tones and neighbor tones are the two most common nonharmonic tones. Both are approached and resolved by step, but they move in different directions. A passing tone fills the space between two different chord tones by moving stepwise in one direction. A neighbor tone leaves a chord tone by step and returns to the same chord tone. Rhythmic placement determines whether each is accented (on the beat) or unaccented (between beats), and that distinction is part of the label.

• Passing tone: Approached by step and resolved by step in the same direction, connecting two different chord tones. Can be diatonic or chromatic.
• Neighbor tone: Approached by step from a chord tone and resolved by step back to the same chord tone. Upper neighbor moves up; lower neighbor moves down.
• Accented vs. unaccented: An accented nonharmonic tone falls directly on a beat; an unaccented one falls on a weak subdivision between beats.
• Double neighbor tone: A pair of neighbor tones, one above and one below the chord tone, that together ornament a single pitch before it returns.

When writing a bass line in 18th-century chorale style, you can add unaccented eighth-note passing tones and neighbor tones to enliven a quarter-note framework. The key is choosing spots where the embellishment creates a good relationship with the soprano. Three reliable contexts are: the bass moves against a stationary soprano (two eighth notes in the bass against one quarter note above), the bass moves in parallel thirds or sixths with the soprano, or the bass and soprano engage in a voice exchange.

• Stationary soprano: When the soprano holds a quarter note, the bass can fill in two eighth notes, one of which may be a passing or neighbor tone.
• Parallel thirds and sixths: Bass embellishments that move in parallel thirds or sixths with the soprano are stylistically correct and create smooth contrary or similar motion.
• Voice exchange: The soprano and bass swap chord tones across a beat, often with a passing tone in the bass filling the gap between the exchanged pitches.
• Unaccented placement: In chorale-style bass writing, passing and neighbor tones are placed on the weak eighth-note subdivision, not on the beat.

These four nonharmonic tone types each have a distinct approach-and-resolution profile. An anticipation arrives early on a weak beat, sounding a note that belongs to the next chord before that chord arrives. An escape tone (echappee) is approached by step and then leaps away to a chord tone in the opposite direction. An appoggiatura is approached by leap and resolved by step, and it typically falls on a strong beat, creating noticeable dissonance. A pedal point is a sustained or repeated pitch, usually in the bass, that is held through chord changes above it.

• Anticipation: A nonharmonic tone that sounds a note from the upcoming chord early, typically on a weak beat, then is restated as a chord tone when the new chord arrives.
• Escape tone: Approached by step from a chord tone, then resolved by leap in the opposite direction to a chord tone. The leap away is what distinguishes it from a neighbor tone.
• Appoggiatura: Approached by leap and resolved by step, usually on a strong beat. Creates a prominent dissonance that resolves to a chord tone.
• Pedal point: A sustained or repeated pitch, most often in the bass, held through harmonies that do not include it as a chord tone. Common at cadential points.

A suspension is a three-stage gesture: preparation (the note is a chord tone), dissonance (the note is held or retied into a new chord where it no longer belongs), and resolution (the note moves down by step to a chord tone). Suspensions are labeled with two numbers showing the interval above the bass before and after resolution, such as 4-3, 9-8, 7-6, and 2-3. A retardation follows the same preparation-dissonance pattern but resolves upward by step instead of downward. On the AP exam, you must identify and notate suspensions; you only need to identify retardations.

• Suspension: A chord tone held over into a new chord as a dissonance, then resolved downward by step. Labeled by interval above the bass: 4-3, 9-8, 7-6, or 2-3.
• Preparation: The note that becomes the suspension must first appear as a consonant chord tone in the preceding chord, often tied across the barline.
• Rearticulated suspension: The suspended note is struck again rather than tied, but it still functions as a suspension because it was a chord tone in the previous harmony.
• Retardation: Like a suspension in preparation and dissonance, but resolves upward by step. You only need to identify these, not write them.
• Figured bass suspension notation: Arabic numerals such as 4-3 in a figured bass indicate a suspension; the first number is the dissonance, the second is the resolution.

A motive is a short melodic or rhythmic idea, often just two to five notes, that serves as a building block for phrases. Composers develop motives by applying transformation procedures that change pitch, rhythm, or both while keeping the idea recognizable. You need to identify the original motive and name the specific procedure used to transform it, both by ear and in notation.

• Fragmentation: A portion of the motive is isolated and repeated or developed on its own, creating a sense of compression or intensification.
• Melodic inversion: The intervals of the motive are flipped: where the original ascends, the inversion descends by the same interval, and vice versa.
• Retrograde: The motive is stated backward, reversing the order of its pitches and rhythms.
• Augmentation: The rhythmic values of the motive are lengthened proportionally, making the idea move more slowly.
• Diminution: The rhythmic values of the motive are shortened proportionally, making the idea move more quickly.

A melodic sequence occurs when a short melodic segment is stated and then immediately repeated at a higher or lower pitch level, with the interval of transposition staying constant across each repetition. For example, a segment that first moves up a third will continue to be transposed up a third with each new statement. Melodic sequences can be diatonic (adjusted to stay in key) or real (exact transposition that may introduce accidentals). Sequences often pair with a corresponding harmonic sequence in the bass or inner voices.

• Melodic sequence: A melodic segment repeated immediately at a consistent interval of transposition, either ascending or descending.
• Interval of transposition: The fixed interval by which the segment moves with each repetition, such as always up a third or always down a second.
• Diatonic (tonal) sequence: The segment is transposed within the key, so interval sizes may vary slightly to avoid accidentals.
• Real (exact) sequence: The segment is transposed exactly, preserving all interval sizes and potentially introducing chromatic pitches.

A harmonic sequence occurs when a group of chords is repeated immediately at a consistent interval of transposition. The root motion pattern stays the same across each repetition, such as always descending by fifth or always moving by thirds. Harmonic sequences are common in Baroque and Classical music and often generate a sense of directed motion through a key. They frequently appear alongside a melodic sequence in the soprano or another voice. You need to identify and apply harmonic sequences in both performed and notated music.

• Harmonic sequence: A chord segment repeated immediately at a consistent interval of transposition, maintaining the same root motion pattern each time.
• Descending-fifths sequence: Root motion moves down by fifth (or up by fourth) with each chord, producing a circle-of-fifths pattern through the key.
• Sequential root motion by thirds: Chords move up or down by thirds in a repeating pattern, a common Baroque and Classical device.
• Diatonic vs. real harmonic sequence: A diatonic sequence adjusts chord quality to stay in key; a real sequence transposes exactly and may leave the key.