Unit 5: Harmony and Voice Leading II: Chord Progressions and Predominant Function

Functional Harmony and Why Chords Move the Way They Do

In common-practice tonal music (the style AP Music Theory most often assesses in part-writing and analysis), chords don’t usually appear in random order. They behave like characters in a story: some chords feel like “home,” some feel like “away from home,” and some create strong tension that demands resolution. Functional harmony is the system that explains these roles and the most typical ways chords connect.

The three core functions: tonic, predominant, dominant

You can understand most tonal progressions through three main categories of harmonic function:

• Tonic function (T): stability and rest; it confirms the key and feels like “home.”
• Predominant function (PD): motion and preparation; it leads away from tonic and sets up dominant. (You’ll also see this called pre-dominant because it prepares the dominant.)
• Dominant function (D): the strongest tension; it points back to tonic and makes the resolution feel inevitable.

A useful mental model is that many phrases follow a large-scale arc:

T → PD → D → T

This is not the only possibility, but it is the most typical backbone for AP-style chorale phrases.

Why function matters for AP Music Theory

When you write or analyze SATB harmony, the goal isn’t just “pick chords that contain the melody notes.” You’re also expected to choose chords that make musical sense as a progression. Function helps you:

• predict what chord types are likely at each moment in a phrase,
• avoid “backwards” chord motion that weakens tonality,
• choose inversions that smooth the bass line and support good voice leading.

Root motion and the “strength” of progressions

Chord successions differ in how strongly they project direction. In tonal harmony, some root motions sound especially goal-directed:

• Descending fifth / ascending fourth root motion (like ii → V, or IV → vii°) is among the strongest because it aligns with the circle of fifths.
• Stepwise root motion can work well too, especially when supported by good voice leading and common tones.

AP doesn’t require you to memorize a single “allowed list” of root motions, but you should internalize a big idea: predominants normally lead to dominants, and dominants normally resolve to tonics.

Harmonic syntax: avoiding “retrogression”

Retrogression is when harmonic function moves in an atypical backward direction (for example, dominant moving to predominant in a way that undermines the cadence). In common-practice style:

• Moving PD → D is expected.
• Moving D → T is expected.
• Moving T → PD is common (you leave home).
• Moving D → PD is usually suspicious unless it’s clearly part of a sequence, a tonicization, or a reinterpreted function.

This matters on AP Free-Response part-writing: even if every chord is spelled correctly, you can still lose points if the progression doesn’t follow stylistic norms.

How voice leading supports harmonic function

Functional harmony is not just about chord labels—it’s also about how individual lines behave.

• Predominant chords often introduce scale degrees that “aim” toward dominant and then resolve in tonic.
• Dominant chords contain the strongest tendency tones (especially the leading tone in major/minor keys), which must resolve correctly for a convincing cadence.

In Unit 5, you zoom in on the middle stage of the phrase—the predominant area—and learn how it propels the harmony toward dominant.

Exam Focus

• Typical question patterns:
  • Identify chord function (T, PD, D) from Roman numerals in a progression.
  • Choose the most stylistically appropriate chord to follow a given tonic harmony and melody note.
  • Error-detection prompts where a “wrong-sounding” chord order reveals a functional issue.
• Common mistakes:
  • Treating Roman numerals as isolated labels instead of hearing/recognizing function (especially missing that ii and IV are typically predominant).
  • Writing progressions that “stall” on tonic too long without a clear PD → D setup.
  • Inserting a predominant after a dominant right before a cadence without a convincing reason.

Predominant Function: What It Is and What It Does

Predominant function refers to harmonies that typically come before dominant harmonies and prepare them. It is also known as the pre-dominant function because it prepares the listener for the dominant chord. Think of predominant as the musical equivalent of “taking a deep breath” before speaking a decisive sentence: it creates motion away from tonic and sets up the arrival of dominant so the cadence feels earned.

A practical way to think about how predominant works is that it often relies on chords that are closely (harmonically) related to dominant—most importantly, the subdominant and supertonic families—so the move into V or V7 feels inevitable.

How to recognize predominant function

In major and minor keys, the most common predominant triads are built on scale degrees that naturally lead to dominant:

• ii chord (built on scale degree 2)
• IV chord (built on scale degree 4)

In minor, you also commonly see:

• iv (minor subdominant)
• ii° (diminished supertonic; sometimes written informally as “ii0”)

These chords share a family resemblance: they often contain scale degree 4 and/or 2, tones that connect smoothly into dominant sonorities.

Why predominant chords feel like “preparation”

Predominant chords help in two main ways:

1. They increase harmonic momentum. After tonic, predominant adds contrast and motion. If you go straight from tonic to dominant every time, the harmony can feel abrupt or overly predictable.
2. They set up the dominant’s tendency tones. Many predominant chords contain tones that will either become common tones in the dominant (especially when using V7), or move by step into tones of the dominant.

Predominant chords are also a classic way to shape tension and release: tonic is stable, predominant increases motion, dominant heightens tension, and tonic releases it.

The two “workhorse” predominant triads in major

In a major key (use C major as a concrete reference):

• ii is D–F–A
• IV is F–A–C

Both are strongly associated with moving to V (G–B–D) or V7 (G–B–D–F).

Notice something important: ii shares two common tones with V7 in C major (F and D are in both ii and V7). That makes ii especially effective at “feeding into” a dominant seventh chord.

Predominant in minor: iv and ii°

Minor keys add two classic predominant colors:

• iv (subdominant minor triad): in A minor, iv is D–F–A.
• ii° (diminished supertonic): in A minor, ii° is B–D–F.

The diminished ii° chord is more tense by nature, so in chorale-style writing it is very commonly used in first inversion (ii°6), which softens the effect and improves voice leading.

Predominant vs. “subdominant”

You’ll often hear people say “subdominant” when they mean “predominant.” They overlap but aren’t identical:

• Subdominant can mean the scale degree (4) or the IV chord specifically.
• Predominant is a function category that includes IV, ii, and related chords.

On AP questions, it’s usually safest to use “predominant” when you’re talking about function (what the chord does) and reserve “subdominant” for IV or scale-degree language.

Predominant placement in a phrase

In a typical phrase with a cadence, predominant harmonies often appear:

• after the opening tonic area,
• in the approach to a cadence (especially an authentic cadence),
• sometimes twice: a first predominant that leads to a half-cadence, and a later one that leads to a stronger authentic cadence.

The big stylistic expectation is: predominant leads into dominant. Even when composers decorate or extend the predominant area, the goal is usually to intensify the approach to V or V7.

Exam Focus

• Typical question patterns:
  • Given a short progression, label which chord(s) function as predominant.
  • In Roman numeral analysis, explain why a chord is interpreted as ii vs. IV based on context.
  • In part-writing, choose between ii and IV (or ii° and iv in minor) as the best predominant for a given bass and soprano.
• Common mistakes:
  • Treating iii or vi as predominant by default (they can appear, but ii and IV are the primary predominant chords in this unit’s typical progressions).
  • In minor, forgetting that the supertonic triad is diminished (ii°), not minor (ii).
  • Calling any “pre-dominant sounding” chord IV without checking the actual pitch content.

The ii Chord Family: Building, Labeling, and Hearing It

The supertonic chord (ii) is one of the most important predominant harmonies because it points so strongly toward dominant—especially when the dominant is a seventh chord. It’s also a staple of the common ii–V–I progression, which shows up in many styles (including tonal classical and later jazz-influenced contexts), and is a useful shorthand for hearing “predominant → dominant → tonic.”

What ii is (and how it’s built)

A diatonic ii triad is built on scale degree 2 using only notes from the key:

• In major: ii is minor (because scale degree 2 to 4 forms a minor third).
• In minor: ii is diminished (ii°) in the natural minor collection.

Examples:

• C major: ii = D–F–A (minor)
• A minor: ii° = B–D–F (diminished)

Why ii is such a strong predominant

The ii chord is effective because of how its tones connect to dominant harmony:

• In major, ii shares tones with V7 (in C: D and F are in both ii and V7).
• Even when the dominant is just V (a triad), ii still tends to move smoothly into it by stepwise voice leading.

This gives you a practical writing advantage in SATB: you can often move from ii (or ii6) to V7 with minimal voice motion, which helps avoid awkward leaps and forbidden parallels.

ii vs. IV: similar role, different flavor

Both ii and IV are predominant, but they don’t behave identically.

• ii often sounds more “directed” and intense, especially in the approach to a cadence.
• IV can sound broader or more spacious, and it often includes the tonic pitch (scale degree 1) as a chord member, which can make it feel less urgent.

In chorale-style phrases, ii (especially ii6) is extremely common right before V or V7.

Common ii progressions you should internalize

These are not rigid formulas, but they are common enough that AP-style writing frequently resembles them.

In major:

• I → ii6 → V → I
• I → ii6 → V7 → I
• I6 → ii6 → V → I

In minor:

• i → ii°6 → V → i
• i → iv → V → i (iv is also predominant, but ii°6 is very characteristic)

Worked example: identifying ii in context

Suppose you’re in C major and you see these chord tones vertically:

• D in the bass
• F, A, and D above

That sonority is clearly D–F–A (with a doubled D), which is ii in C major.

Now imagine the next chord is G–B–D–F (V7). The voice-leading can be extremely smooth:

• D can stay D (common tone)
• F can stay F (common tone)
• A can move to G (step)

This “two common tones” connection is one reason ii is such a dependable predominant.

What goes wrong with ii

Two frequent style issues show up when students first use ii:

1. Using ii in root position in a way that makes the bass line clunky. Root-position ii (with scale degree 2 in the bass) can be fine, but it often creates bigger leaps in the bass than ii6 does.
2. In minor, forgetting the raised leading tone in V while also mishandling ii°. If you’re in A minor, V should use G-sharp, but ii° is still spelled with B–D–F (diatonic to the natural minor). The key signature alone doesn’t tell you everything; harmonic function does.

Exam Focus

• Typical question patterns:
  • Roman numeral analysis: label ii or ii° correctly and identify inversion via figured bass.
  • Part-writing: insert a predominant chord between tonic and dominant (ii6 is often the best choice).
  • Multiple-choice: hear/recognize the predominant sound and select the correct chord label.
• Common mistakes:
  • Labeling ii° in minor as ii (forgetting the diminished fifth).
  • Treating ii as a tonic substitute (it can prolong pre-dominant area, but it normally doesn’t replace tonic function at phrase beginnings).
  • Doubling unstable tones in diminished chords without understanding safer doubling choices (addressed more in the inversion/voice-leading section).

The IV and iv Chords: Subdominant Color and Function

The subdominant chord is the chord built on the fourth scale degree of a major or minor key. In functional terms, IV (in major) and iv (in minor) are core predominant harmonies: they commonly lead to the dominant and help create motion, tension, and eventual release.

What IV/iv is

• IV (major key): built on scale degree 4 using notes from the major scale (a major triad).
• iv (minor key): built on scale degree 4 using notes from the minor scale (a minor triad).

Examples:

• C major: IV = F–A–C
• A minor: iv = D–F–A

Why IV can feel less “urgent” than ii

A key feature of IV in major is that it contains scale degree 1 (the tonic note). In C major, IV contains C. That shared pitch can make IV sound somewhat connected to tonic—still predominant, but sometimes gentler than ii.

This is not a rule that IV is “weaker,” but it helps explain common stylistic choices:

• Approaching a strong cadence: ii (often ii6) is extremely common.
• In broader phrases or hymn-like textures: IV is common and effective.

Typical uses of IV and iv

1. As a predominant moving to V

   • I → IV → V → I is a foundational progression.
   • IV is also commonly part of patterns that lead to dominant, including the broader idea of ii–V–I (where ii and IV are both predominant-family options).

2. As a predominant in a plagal context

   • IV → I is the classic “Amen” sound (a plagal motion).
   • Be careful: IV → I is not predominant → dominant → tonic; it’s its own kind of cadential gesture and usually doesn’t replace authentic cadence strength.

3. In minor, iv as a strong predominant

   • i → iv → V → i is extremely idiomatic.
   • The iv chord supports smooth voice leading into V, especially when V is major (with raised leading tone) and iv is minor.

Worked example: IV leading to V in SATB (conceptual)

In C major:

• IV = F–A–C
• V = G–B–D

Smooth voice-leading often includes:

• F moving to G (step up)
• A moving to G or B (step down or up)
• C typically moving down to B (step) as you approach V; this specific tendency (scale degree 1 down to scale degree 7) is one common reason IV → V feels directed.

The key is to avoid parallel perfect fifths/octaves and to keep common tones when they exist (more common with ii → V7 than IV → V7).

Common pitfall: treating IV as a tonic substitute

Because IV shares a note with I and can sometimes sound “stable,” students sometimes use it where tonic is expected (like at the very end of a phrase). In common-practice harmony, IV at the end typically sounds unfinished unless it is part of a deliberate plagal ending or a larger context.

Exam Focus

• Typical question patterns:
  • Identify IV or iv in Roman numeral analysis and determine its function.
  • Part-writing: choose IV vs. ii6 as the predominant based on given bass motion.
  • Aural multiple-choice: recognize the characteristic iv color in minor.
• Common mistakes:
  • Using IV to end an authentic cadence (it weakens the cadence unless the question explicitly aims for a plagal gesture).
  • In minor, accidentally using IV (major) when the context expects iv (minor), or vice versa.
  • Forgetting that IV/iv is predominantly a preparation for dominant, not a replacement for it.

Inversions of Predominant Chords: Figured Bass, Bass Lines, and Voice-Leading Benefits

In chorale-style writing, inversions are not just “alternate spellings.” They are tools that help you control the bass line and reduce voice-leading problems. Predominant chords are especially likely to appear in inversion, particularly first inversion.

What inversion means in this unit

A triad’s inversion depends on which chord member is in the bass:

• Root position: root in bass (figured bass 5/3, often not written)
• First inversion: third in bass (6)
• Second inversion: fifth in bass (6/4)

AP expects you to identify inversion using both:

• Figured bass (6, 6/4)
• Bass note recognition (which chord member is in the bass)

Why first inversion predominants are so common

First inversion predominant chords—especially ii6 and ii°6—show up constantly because they solve multiple problems at once.

1. They smooth the bass line. In major, going I (scale degree 1 in bass) to ii6 puts scale degree 4 in the bass, which often creates stepwise or gently moving bass patterns into V.
2. They reduce the heaviness of unstable chords. In minor, ii° in root position can sound harsh and can create tricky doublings; ii°6 is more controlled and idiomatic.
3. They help avoid parallels. Some root-position successions create parallel fifths/octaves more easily in SATB; switching to first inversion often fixes that while preserving function.

ii6 in major: what it is and why it works

In C major:

• ii = D–F–A
• ii6 means F is in the bass (because F is the third of the chord)

So ii6 is spelled with chord tones D–F–A but with F as the lowest voice.

A common bass pattern is:

• I (C in bass) → ii6 (F in bass) → V (G in bass) → I (C in bass)

That bass motion C → F → G → C outlines strong functional steps and often feels more singable than C → D → G → C.

ii°6 in minor: the standard predominant in minor chorales

In A minor:

• ii° = B–D–F
• ii°6 means D is in the bass (third of the chord)

This chord is extremely common right before V (E–G#–B) or V7 (E–G#–B–D). Notice a particularly elegant connection: D is common between ii°6 and V7 in A minor (since D is the seventh of V7).

Doubling guidelines (and why they matter)

In SATB, you usually double a chord tone to make four voices. Doubling isn’t arbitrary; the doubled note affects stability and voice-leading.

General stylistic tendencies for this unit:

• Avoid doubling the leading tone (scale degree 7) because it has a strong tendency to resolve and doubling it increases the chance of incorrect resolution.
• In first inversion triads, doubling is more flexible than in root position. Often you double the soprano note if it’s a stable chord tone.
• For diminished triads (like ii° in minor), a common safe choice is to double the third of the chord (the bass note in first inversion). This helps avoid emphasis on the diminished fifth relationship.

These are not “physics laws,” but they are strong style norms that keep you out of trouble on AP part-writing.

Second inversion predominants: proceed carefully

Second inversion triads (6/4) are considered less stable in common-practice harmony. In many AP-style contexts, 6/4 sonorities are treated as embellishing harmonies rather than independent functional chords.

In Unit 5, the most relevant idea is that if you see a 6/4 near a cadence, it is often part of a cadential dominant expansion (commonly taught as a cadential 6/4). The key habit is: don’t assume every 6/4 is a “real” predominant just because it uses notes that could spell a IV or ii chord. Always check context, bass position, and resolution.

Mini worked example: labeling inversion with Roman numerals

In C major, suppose the chord tones are F–A–D, with F in the bass.

• The chord is D–F–A (ii)
• F in bass means first inversion
• Roman numeral: ii6

If you see B–D–F with D in bass in A minor:

• chord is B–D–F (ii°)
• D in bass means first inversion
• Roman numeral: ii°6

Exam Focus

• Typical question patterns:
  • Given a bass note and chord members, label inversion accurately (ii vs. ii6, iv vs. iv6).
  • Part-writing prompts that strongly imply ii6 or ii°6 as the predominant before V.
  • Error detection: wrong doubling or awkward spacing in a predominant chord.
• Common mistakes:
  • Mislabeling inversion because you identify the chord by the soprano instead of the bass.
  • Doubling the leading tone in minor when V is present (for example, doubling G# in A minor dominant harmony).
  • Treating 6/4 chords as stable triads rather than as context-dependent embellishments.

Voice Leading Through Predominant Harmony in SATB

Predominant function is not just a Roman numeral choice; it’s a voice-leading environment. In AP free-response, many point losses come from voice-leading errors that happen right as students move through the predominant into dominant.

The core goals of good voice leading

In chorale-style SATB, you are usually aiming for:

1. Smooth individual lines (especially soprano and bass): mostly stepwise motion with occasional tasteful leaps.
2. Correct tendency-tone resolution: especially the leading tone and chordal sevenths (when present).
3. No forbidden parallels: avoid parallel perfect fifths and octaves between any pair of voices.
4. Good spacing and range: keep upper three voices within an octave of each other (typical guideline) and stay within singable ranges.

Predominant chords can help with smoothness because they often connect by common tones or steps into dominant.

Common-tone strategy: make the progression feel inevitable

When moving from predominant to dominant (especially ii to V7), look for:

• notes that can stay the same,
• notes that can move by step,
• places where a leap is unavoidable (usually best kept in the bass).

For example, ii → V7 often allows multiple common tones; IV → V usually does not. That means ii is often the “low-friction” choice right before a cadence.

Practical voice-leading guidelines into V7

When moving from a predominant chord to a V7 chord, a few common stylistic moves help the progression sound directed:

• Aim for stepwise motion into the V7 chord wherever possible by moving voices to their nearest chord tone in V7.
• In progressions involving IV (or iv) going to V7, it’s very common for the chord member that is scale degree 1 (often the fifth of IV/iv) to move down by step to the note that becomes the third of V7 (the leading tone of the key). This is a frequent, idiomatic way to intensify the pull into dominant.
• Even though the leading tone is usually introduced as part of dominant harmony, remember the essential tendency-tone goal: the leading tone (scale degree 7) resolves up to tonic (scale degree 1) at the cadence. Your predominant voicing choices should make that resolution easy and unforced.

Handling the tendency tones around predominant → dominant → tonic

Even though the strongest tendency tones live in dominant harmony, predominant sets them up.

• In major keys, scale degree 4 is frequently present in ii or IV and becomes especially significant if it appears as the chordal seventh of V7 (since that seventh must resolve downward by step in the following tonic harmony).
• In minor keys, the raised leading tone in V (scale degree 7 raised) must resolve up to tonic (scale degree 1) in a convincing authentic cadence.

A common conceptual mistake is to think “predominant doesn’t have tendency tones, so I can move voices however I want.” In reality, predominant is where you prepare the clean resolutions that will be required in dominant and tonic.

Part-writing choice: ii6 vs. IV

When a prompt asks you to “complete the progression” or harmonize a melody, you often have options. Here’s how you decide in a principled way:

• Choose ii6 when you want:

  • a smoother bass line into V,
  • an efficient approach to V7,
  • a more cadence-driven, directed predominant.

• Choose IV when:

  • the melody strongly suggests IV tones,
  • the phrase wants a broader predominant area,
  • the bass motion supports it cleanly.

What you should avoid is choosing randomly. On AP FRQs, “stylistic plausibility” is part of what you are being assessed on.

A worked SATB-style progression (text-based) in C major

Goal: create a basic phrase skeleton with a predominant.

Progression: I → ii6 → V7 → I

• I (C–E–G)
• ii6 (D–F–A with F in bass)
• V7 (G–B–D–F)
• I (C–E–G)

One voice-leading approach (not the only correct one):

• Keep F as a common tone from ii6 to V7 (it is the 7th of V7).
• Move A down to G (step).
• Keep D as a common tone from ii6 to V7 (it is the 5th of V7).
• Then resolve the V7 properly to I:
  • F (the chordal 7th of V7) resolves down to E.
  • B (leading tone) resolves up to C.

Notice how the predominant chord makes the V7 resolution almost “pre-loaded”: you already have the tones that need to resolve.

What goes wrong most often in predominant voice leading

• Parallel fifths created by “similar motion” into V. Students sometimes move multiple voices in the same direction into the dominant, accidentally aligning perfect intervals.
• Leapy inner voices. Alto and tenor should generally move by step or small intervals; large leaps there often sound unstylistic and increase parallel risk.
• Forgetting to resolve the seventh of V7 because attention is focused earlier on choosing the predominant.

Exam Focus

• Typical question patterns:
  • SATB part-writing: fill in alto/tenor given soprano and bass with a required predominant harmony.
  • Identify voice-leading errors in a predominant-to-dominant move (parallels, spacing, unresolved tendency tones).
  • Multiple-choice: pick the best harmonization option that uses a predominant correctly.
• Common mistakes:
  • Writing ii in an inversion that makes the bass awkward or creates parallels when ii6 would solve it.
  • Treating V7 resolution rules as optional (unresolved chordal seventh is a frequent scoring issue).
  • Doubling choices that force bad resolutions (especially in minor or diminished chords).

Common Predominant-to-Dominant Patterns and Phrase Models

Once you understand what predominant chords are, the next step is to recognize the most common ways they appear in real phrases—especially as preparation for cadences.

The phrase-model idea: harmonic “zones”

A lot of tonal phrases can be understood as moving through zones:

• Tonic zone: establishes key (I, sometimes I6, sometimes tonic prolongation)
• Predominant zone: moves away and prepares (ii, ii6, IV, iv, ii°6)
• Dominant zone: builds tension (V, V7, and cadential expansions)
• Return to tonic: resolution (I)

Thinking in zones helps on AP questions where you must decide which chord best fits “right now” in the phrase.

The approach to a cadence: why predominant is so expected

In a strong cadence—especially a perfect authentic cadence—listeners expect a clear setup:

• predominant creates motion and “readiness,”
• dominant creates urgency,
• tonic resolves.

If you skip predominant entirely, the cadence can still work, but it often feels less prepared. In chorale-style writing, that preparation is part of the style.

Typical cadential approach patterns (major)

These patterns appear frequently in AP-style contexts:

1. I → ii6 → V → I
2. I → ii6 → V7 → I
3. I → IV → V → I

In many hymn textures, you’ll see IV used earlier in the phrase and ii6 used closer to the cadence.

Typical cadential approach patterns (minor)

Minor-key cadences usually include a major V (or V7) with a raised leading tone, even though the key signature might suggest otherwise.

Common patterns:

1. i → ii°6 → V → i
2. i → iv → V → i

A common misconception is that “everything must stay in natural minor.” Functional harmony usually overrides that: the dominant is typically altered to be major (harmonic minor behavior) because it strengthens the cadence.

Predominant expansion: extending the preparation

Composers don’t always use a single predominant chord and immediately go to V. They often expand the predominant area to build a longer approach.

Ways predominant can be expanded in a basic diatonic style:

• Prolonging one predominant harmony with passing or neighbor tones in one or more voices.
• Moving between predominant chords (for example, IV to ii6, or ii6 to IV6) to create harmonic motion while still staying in the PD zone.

The key is that the harmony still behaves like preparation; it hasn’t entered dominant function yet.

A worked analysis example: identifying zones

Consider this Roman numeral plan in G major:

• I | I6 | ii6 | V7 | I

Zone interpretation:

• I and I6: tonic zone (establishes and slightly decorates tonic)
• ii6: predominant zone
• V7: dominant zone
• I: return to tonic

This kind of labeling helps you answer “what function is this chord serving?” even if the chord is inverted or decorated.

Exam Focus

• Typical question patterns:
  • Given a melody and a cadence goal, choose a predominant harmony that best prepares the dominant.
  • Analyze a phrase and mark where predominant function begins.
  • Multiple-choice: identify which progression sounds most stylistically correct (often the one with clear PD → D motion).
• Common mistakes:
  • Jumping to dominant too early (creating a dominant zone that’s too long or unsupported).
  • Using predominant chords after the dominant right before resolution, weakening the cadence.
  • In minor, failing to raise the leading tone in V/V7 during the dominant zone.

Sequential and Circle-of-Fifths Motion: How Predominants Create Harmonic Momentum

A powerful way tonal music builds forward motion is through sequences, especially those that follow the circle of fifths. While Unit 5 focuses on predominant function, it’s important to see that predominant chords often participate in these patterns because they naturally connect with strong root motion.

What a harmonic sequence is

A sequence is a pattern that repeats at different pitch levels. In harmony, that often means:

• a repeating chord progression model transposed up or down,
• a repeating bass-line pattern,
• a repeating voice-leading pattern.

Sequences matter because they create predictable forward momentum. Even if you don’t name every chord perfectly at first, you can often identify a sequence by the repeated intervallic pattern.

Circle-of-fifths (descending fifths) sequences

A very common sequential root pattern is descending by fifth (or ascending by fourth). In Roman numerals, a diatonic version in a major key might look like:

• I → IV → vii° → iii → vi → ii → V → I

Not every piece uses the full chain, but shorter segments are extremely common, such as:

• vi → ii → V → I

Notice how ii appears near the end of the chain as a predominant that leads strongly to V.

Why this relates to predominant function

Even though a circle-of-fifths sequence contains a variety of chords, it often creates the sense of a growing predominant/dominant pull toward a cadence. You can think of it as gradually increasing directed motion until the cadence arrives.

In many contexts, ii is the last and clearest predominant step before the dominant.

How to analyze sequences without getting lost

When you encounter a string of chords in analysis:

1. Look at the bass line (or the roots if they’re clear). Are they moving by fifths or repeating a pattern?
2. Identify where the phrase is headed. Does the sequence aim toward a cadence?
3. Find the point where predominant becomes dominant (often where V or V7 arrives and cadence behavior begins).

A common student error is to label every chord correctly but miss the bigger story: sequences are often about momentum, not just chord identity.

Simple worked example: spotting a vi–ii–V–I approach

In C major, a common cadential drive is:

• Am (vi) → Dm (ii) → G7 (V7) → C (I)

Even if you don’t remember every chord quality, the functional arc is clear:

• vi can act as a tonic-area substitute or a pre-predominant color,
• ii is the predominant,
• V7 is dominant,
• I resolves.

This is one reason ii is so central: it’s the “launchpad” into the dominant.

Exam Focus

• Typical question patterns:
  • Identify sequential patterns and determine which chord is acting as the predominant right before the cadence.
  • Multiple-choice listening: recognize the drive of circle-of-fifths motion.
  • Roman numeral analysis of a short excerpt that includes a partial fifths sequence ending in ii–V–I.
• Common mistakes:
  • Misidentifying function because you focus on one chord at a time instead of hearing the sequence’s direction.
  • Losing the key center and labeling chords as if the sequence modulates when it may not.
  • Forgetting that a sequence can include predominant chords but is not “all predominant”—function still shifts as the cadence approaches.

Applying Predominant Function in AP Free-Response: Strategy and Common Traps

Unit 5 concepts show up heavily when you have to do harmony: harmonize a melody, complete a part-writing progression, or analyze a chorale-style excerpt. Predominant function is often the hinge between “establish the key” and “make a cadence.” A common practical task is adding predominant harmonies—especially IV (iv) and ii (ii°)—to a melodic phrase so the approach to dominant sounds stylistically prepared.

Where predominant decisions show up in part-writing prompts

In a typical SATB free-response task, you might be given:

• a soprano line and a bass line, plus Roman numerals,
• or a melody with implied harmony and a cadence target,
• or a partially completed chorale where you must fill missing chords.

Predominant is often the spot where you have genuine choice (ii vs. IV; ii6 vs. ii), and your choice affects whether the rest of the progression can be voice-led cleanly.

A practical decision process for choosing a predominant chord

When you need to choose a predominant harmony, ask:

1. What chord tones does the melody already give me?
   • If the soprano has scale degree 4 or 2, ii or IV may be natural.
2. What bass motion is most natural?
   • If you want smooth bass into V, ii6 (or ii°6 in minor) is often ideal.
3. Am I approaching a cadence right now?
   • Closer to a cadence, ii (especially ii6) is extremely common.
4. Will this choice create parallels into V?
   • Try out the likely voice-leading paths; if one option produces parallel fifths/octaves, use the other or adjust inversions.

This is what “thinking like a tonal composer” looks like on the exam.

Common errors specific to predominant progressions

1. Weak or missing predominant before a cadence

Students sometimes go:

• I → V → I

This can be acceptable in some contexts, but in chorale-style writing it often sounds underprepared unless it’s very short or stylistically justified. Adding a predominant typically strengthens the phrase:

• I → ii6 → V → I

2. Incorrect handling of minor-key dominant preparation

In minor, you must balance two truths:

• Predominant chords like iv and ii°6 are usually diatonic to the key signature.
• Dominant chords usually require the raised leading tone.

If you keep everything in natural minor, the dominant becomes minor (v), and the cadence loses strength. AP-style writing expects you to understand that functional dominant typically uses raised 7.

3. Inversion mislabeling and “bass-blindness”

A frequent analysis mistake is labeling ii when the sonority is actually ii6 because you identify the chord by the soprano note. On AP, inversion is determined by the bass. Train yourself to check the bass first.

4. Voice-leading errors caused by rushed predominant placement

Students often focus so hard on “getting a predominant chord in there” that they:

• create parallel fifths into V,
• double an unstable tone,
• or trap an inner voice in an awkward leap.

The fix is to treat predominant as part of a line-leading plan, not just a harmonic label.

Mini worked scenario: choosing between IV and ii6

Imagine you’re in C major, approaching a cadence, and the bass goes:

• C (I) → F ( ? ) → G (V)

Because the bass is F, the most natural predominant is ii6 (F in the bass is the third of ii). IV in root position would also have F in the bass, so you must check chord members:

• If the upper voices include A and C, that spells IV.
• If the upper voices include D and A, that spells ii6.

Both can work, but ii6 → V is often the more strongly directed cadential preparation, especially if you plan to use V7.

Exam Focus

• Typical question patterns:
  • Free-response part-writing: include a predominant in the middle of a phrase and maintain proper voice-leading into V or V7.
  • Roman numeral analysis: identify predominant chords and explain their function in context.
  • Multiple-choice: choose the best harmonization that uses a predominant appropriately before a cadence.
• Common mistakes:
  • Choosing a predominant chord that fits the soprano but clashes with the bass or forces parallels.
  • In minor, writing v instead of V at cadences (missing the raised leading tone expectation).
  • Mismanaging inversions: writing ii when the bass clearly indicates ii6 (or vice versa).