Harmonic punctuation: how phrases stop, pause and surprise
Welcome back to Harmony Spiral!
Every sentence you read ends with a mark: a full stop, a comma, a question mark. Music has the same marks, and they are made of chords. A cadence is the pair (or small group) of chords that closes a phrase and tells the ear whether the music has finished, paused, or taken a turn.
In this chapter we learn the classic cadences (authentic, plagal, half, deceptive, Phrygian), hear exactly which notes move (7 → 1, 4 → 3) to make them work, and then see how the same tools shape minor keys and today's popular music.
A cadence is the chord progression that ends a musical phrase: the harmonic punctuation mark. Just as a sentence can end in a full stop or pause on a comma, a phrase can end feeling finished or feeling open, and the last two chords decide which.
Full stop (.)
The phrase lands on the tonic I. Nothing more is needed.
Comma (,)
The phrase stops on the dominant V. The ear waits for more.
Plot twist (!)
The dominant V resolves somewhere unexpected.
Listen to the same short melody twice. Ending on degree 1 (the note C in C major) sounds complete. Ending on degree 2 (the note D) sounds like the sentence is still in the air. Cadences do exactly this with chords instead of single notes.
The authentic cadence moves from the dominant to the tonic, V → I, and it is the strongest way to end a phrase in tonal music. In C major that is G → C. Add the seventh and it becomes G7 → C.
V → I V7 → I
The authentic cadence. In C major: G → C, G7 → C
Why does it feel so final? Because the notes inside V7 are pulling. G7 is 1 3 5 b7 on G: the notes G B D F. Measured in the key of C, those are degrees 5 7 2 4, and two of them are the tendency tones we met in the scale chapter.
| Note in G7 | Degree in C | Moves to | Motion | Hear it |
|---|---|---|---|---|
| 7 (leading tone) | 7 → 1, up a minor second | |||
| 4 | 4 → 3, down a minor second | |||
| 2 | 2 → 1, down a major second | |||
| 5 | 5 stays, the common tone |
The tritone resolves
B and F are a tritone apart, the most unstable interval in the key (an augmented fourth, six semitones). In G7 → C they collapse inward onto C and E, a third. That inward squeeze is the engine of the authentic cadence, and it is why V7 sounds even more decisive than plain V.
Not every V → I is equally final. A perfect authentic cadence (PAC) is the strongest possible ending: both chords in root position and the melody, the top note, landing on degree 1. Change any one of those and you have an imperfect authentic cadence (IAC).
| PAC | IAC | |
|---|---|---|
| Bass of V and I | root position (G, C) | one of them inverted (e.g. G7/B) |
| Top note of I | degree 1 (C) | degree 3 or 5 (E or G) |
| Hear it | ||
| Feeling | final: the end of a piece or section | conclusive but softer, inside a phrase |
Listen carefully to the top note. In the PAC the melody arrives on C, degree 1: the door closes. In the IAC the same chords are there, but the melody stops on E (degree 3) or G (degree 5). The chord is home, the melody is not quite. Putting the leading tone B in the bass (G7/B → C) softens it the same way.
Composers use the PAC for the big arrivals and IACs for the smaller ones. Spotting which is which tells you the shape of a whole piece: the strongest full stop is always a PAC.
The plagal cadence ends a phrase from the subdominant: IV → I. It is the "Amen" sung at the end of hymns. In C major, F → C.
IV → I
The plagal cadence. In C major: F → C. In A minor: Dm → Am
Compare its voice motion with the authentic cadence. F is 1 3 5 on F: the notes F A C, degrees 4 6 1 in C. There is no leading tone and no tritone, so nothing is being squeezed:
| Note in F | Degree in C | Moves to | Motion | Hear it |
|---|---|---|---|---|
| 4 | 4 → 3, down a minor second | |||
| 6 | 6 → 5, down a major second | |||
| 1 | 1 stays, the common tone |
The result is gentler: a settling rather than an arrival. Because the tonic note C is already present in IV, the plagal cadence often comes after an authentic cadence as an extra confirmation. That is exactly what the "Amen" is doing.
A half cadence (HC) is any phrase ending that stops on the dominant V. It is the comma of music: the phrase pauses, but the leading tone is hanging in the air and the ear knows the sentence is not over.
… → V
The half cadence: any approach, ending on V
What comes before the V can vary. The most common approaches in C major:
I → V (C → G): the simplest half cadence. ii → V (Dm → G): the classical favourite. The bass rises a fourth. IV → V (F → G): the bass steps up, strong forward motion. Half cadences are how composers build a question and answer. A first phrase ends on V (HC, the question). A second phrase repeats the idea and ends on I (PAC, the answer). Pause on the G chord below and notice how much you want the C that never comes.
A deceptive cadence (DC) sets up the authentic cadence and then resolves the dominant somewhere other than the tonic, most often to vi. In C major: G7 → Am instead of G7 → C.
V → vi
The deceptive cadence. In C major: G7 → Am
It works because vi is the tonic's closest relative. Am is 1 b3 5 on A, the notes A C E, and it shares C and E with the C chord. The tendency tones still resolve exactly as promised, 7 → 1 (B → C) and 4 → 3 (F → E). Only the bass steps up 5 → 6 (G → A) instead of falling to 1. Everything sounds right except the floor.
A cousin: the evaded cadence
In an evaded cadence the dominant does reach a tonic chord, but a weak one, for example V7 → I/3 (G7 → C/E), with the tonic inverted so it cannot act as a full stop. (A plain V → IV, common in rock, is not a cadence at all but a retrogression: the harmony steps backwards instead of resolving.)
The Phrygian half cadence is a half cadence characteristic of minor keys: the subdominant in first inversion moves to the dominant, iv/3 → V, with the bass sliding down a minor second from b6 to 5. In A minor: Dm/F → E.
iv/3 → V
Phrygian half cadence. In A minor: Dm/F → E (bass F → E)
The whole character lives in the bass. Dm is 1 b3 5 on D, the notes D F A, and putting F (degree b6 of A minor) at the bottom sets up that minor-second drop F → E, a single semitone. Above it, A falls to G# and D moves to B or E. Play the root-position Dm → E for comparison: correct, but the magic is gone.
Why "Phrygian"?
In the Phrygian mode the note a minor second above the tonic (b2) steps down onto it. Here the same step happens onto the dominant: F → E is b2 → 1 if you hear E as the goal. The sound is dark and slightly Spanish, and it is the last step of the descending i-bVII-bVI-V line (Am G F E) heard in flamenco and countless minor-key songs.
The cadential 6/4 is not a new cadence but a decoration of the authentic one: the tonic chord with degree 5 in the bass is placed just before V7, so the dominant arrives in two stages. In C major: C/G → G7 → C.
I/5 → V7 → I
The cadential 6/4. In C major: C/G → G7 → C
Why "6/4"?
The name comes from figured bass, which labels a chord by the intervals above its bass note. With G in the bass, C is a sixth and E a fourth above it, hence "6/4". In this course we write the same chord as a slash chord, C/G, and this is the only place we need the old name.
The trick is that C/G does not sound like a tonic at all. The bass is already on G, so the ear hears a dominant with two suspended notes on top that then fall into place: C → B (1 → 7) and E → D (3 → 2), while the seventh F joins. Only then does G7 resolve to C as usual.
| Voice | I/5 (C/G) | V7 (G7) | I (C) |
|---|---|---|---|
| Bass | |||
| Middle | |||
| Top | |||
| All together |
Cadences in minor keys use the same shapes as in major, with one essential adjustment: the dominant must be a major chord, so degree 7 is raised to make a leading tone. That raised 7 is exactly what turns natural minor into harmonic minor.
1 2 b3 4 5 b6 7
Harmonic minor: natural minor with the 7 raised, so that V is major
In A minor, natural minor gives v = Em (E G B). The G sits a major second below A and hardly pulls. Raise it to G# and V = E (E G# B): now G# → A is 7 → 1, a minor second (the leading tone's single semitone), and the cadence bites. So the minor-key authentic cadence is E → Am or E7 → Am, never Em → Am.
| Cadence | In A minor | Notes |
|---|---|---|
Authentic V7 → i | G# → A is the leading tone; D → C is 4 → b3 | |
Plagal iv → i | darker than in major; F → E is b6 → 5 | |
Half … → V | or the Phrygian version Dm/F → E | |
Deceptive V → bVI | the surprise chord is major here, a brighter twist |
The Picardy third
For centuries, minor-key pieces often ended on a major tonic: E7 → A instead of E7 → Am. Raising the final b3 to 3 (C → C#) is called the Picardy third. The clouds part on the very last chord. Play both endings and listen to how the same cadence changes its mood with one note.
A cadence gets stronger when the dominant is prepared. Placing a pre-dominant chord, ii or IV, before V gives the ear a three-step path home: pre-dominant → dominant → tonic.
ii → V → I IV → V → I
Prepared authentic cadences. In C major: Dm → G → C, F → G → C
ii and IV do the same job because they share two notes: Dm is D F A, F is F A C. Both contain degree 4 (F), which then steps down to 3 when V resolves, and both hand the bass to G: D → G up a fourth, F → G up a step.
ii7 → V7 → Imaj7 (Dm7 → G7 → Cmaj7): the jazz form, the single most-played progression in the repertoire. ii/3 → V7 → I (Dm/F → G7 → C): the classical form, with F in the bass stepping up to G. ii/3 → I/5 → V7 → I (Dm/F → C/G → G7 → C): the full classical formula. The pre-dominant, the cadential 6/4 from the last section, and the resolution. Popular music uses the same cadences but weights them differently: the plagal IV → I is very common, the borrowed bVII → I is a rock signature, and many songs run on four-chord loops that never fully cadence at all.
| Ending | In C major | Character |
|---|---|---|
IV → I | plagal. Open and relaxed, everywhere in rock, gospel, folk | |
bVII → I | borrowed from Mixolydian; no leading tone, a bluesy rock "arrival" | |
bVI → bVII → I | two borrowed chords climbing by major seconds, a triumphant lift | |
V → I | still used, especially in pop ballads and country |
Now the loops. vi-IV-I-V (Am F C G) and its rotation I-V-vi-IV (C G Am F) cycle for a whole song. Look at where the tonic falls: in Am F C G the C sits in the middle and the loop ends on `V`, a permanent half cadence that pushes straight back to the top. Nothing ever closes, and that endless forward lean is the point.
When a looped song does want a real ending, the producer usually breaks the loop: the last chord is held on I, or the track simply fades. That is why so many pop songs end with a sustained tonic chord or no cadence at all.
Step back and the whole of harmony looks like this: chords leave the tonic, gather tension on a pre-dominant, peak on the dominant, and release at a cadence. Tonic → pre-dominant → dominant → tonic is the sentence. The cadence is where it lands.
Tonic
I (or vi, iii): home, stable.
Pre-dominant
ii, IV (or borrowed iv, bVI): leaning away.
Dominant
V, V7, vii°: maximum pull.
Cadence
PAC / IAC / HC / DC / plagal: how the sentence ends.
Everything you learned earlier serves this arc. Applied dominants tonicize a chord on the way, borrowed chords colour the pre-dominant, and inversions decide whether an arrival is a PAC or an IAC. Change the cadence and you change the meaning of every chord that led to it.
In the next chapter we stay on the dominant and look upward. The same G7 → C can carry a whole extra triad on top, for example an A major triad over G7, giving the 9, #11 and 13. These upper structures are how jazz dresses the cadence without changing where it goes. Hear the plain cadence, then the dressed one: same 7 → 1, same 4 → 3, a much bigger sky.
In the next lesson we look at upper structures: triads stacked on top of a dominant seventh to add 9, #11 and 13 without changing where the cadence goes.
V → I / V7 → I: the tritone resolves, 7 → 1 and 4 → 33/5 on top)IV → I (the Amen), half cadence ending on V, deceptive V → vi, evaded V7 → I/3iv/3 → V with the bass b6 → 5I/5 → V7 → IV from harmonic minor, V → bVI, the Picardy thirdii-V-I and IV-V-I; pop endings IV → I, bVII → I and loops that never close