A composer ends the antecedent phrase of a period with a perfect authentic cadence (V–I, both chords root position, soprano on tonic). What structural problem does this create?
ANo problem — a stronger cadence always produces a stronger phrase structure
BThe period is undermined: the antecedent should create an open question, not close definitively; the consequent now has nowhere to go
CA plagal cadence would have been more appropriate for the antecedent
DVoice-leading rules are more difficult to satisfy at a PAC than at a half cadence
In a period, the antecedent phrase creates expectation that the consequent resolves. A half cadence (ending on V) is the standard antecedent ending precisely because it leaves the tonal question open. A perfect authentic cadence provides such strong closure that the consequent feels redundant — as if the music already ended and then continued unnecessarily. Cadence choice is a structural decision about degrees of finality, not just a harmonic labeling exercise.
Question 2 Multiple Choice
Which cadence type is most appropriate for a phrase ending that should function like a semicolon — pausing without concluding?
APerfect authentic cadence — maximum closure is always the safest choice
BPlagal cadence — its mellow 'amen' quality suggests a gentle pause
CHalf cadence — ending on V creates an unstable pause on the dominant that demands continuation
DDeceptive cadence — the surprise of V–vi mimics the unexpected pause of a semicolon
The half cadence (ending on V) is the precise structural analogue of a semicolon: the phrase pauses on an unstable harmony that creates anticipation for what follows. The dominant harmony is inherently unstable and demands resolution to tonic — so ending on it says 'there is more to come.' The plagal cadence (IV–I) actually provides genuine, if mellow, closure. The deceptive cadence redirects rather than pauses.
Question 3 True / False
The deceptive cadence (V–vi) should be treated as a compositional error to be corrected, since it fails to provide closure.
TTrue
FFalse
Answer: False
The deceptive cadence is a deliberate compositional tool with its own structural function: by substituting vi where the ear expects I, it creates a powerful surprise that extends or redirects phrase momentum. Used intentionally, it allows composers to defer closure, build intensity, or create expressive ambiguity. The Explainer distinguishes 'used well' from 'used carelessly' — the deceptive cadence is as legitimate as any other cadence type, and has historically been one of the most expressive harmonic devices available.
Question 4 True / False
A perfect authentic cadence (PAC) and an imperfect authentic cadence (IAC) both use V–I motion, but the PAC provides stronger closure because both chords are in root position and the soprano ends on the tonic.
TTrue
FFalse
Answer: True
This is correct. The strength of closure depends on position and soprano line: a PAC requires both chords in root position and the soprano ending on scale degree 1, maximizing the sense of arrival. An IAC has at least one chord inverted or the soprano ending on a non-tonic chord tone, which weakens the sense of finality while still producing V–I motion. This gradation of closure — PAC strongest, IAC moderate — is a key compositional resource for shaping formal structure.
Question 5 Short Answer
What is the structural logic that should guide a composer's choice of cadence type at a given phrase ending?
Think about your answer, then reveal below.
Model answer: Cadence choice should reflect the desired degree of finality at that formal point. Strong closure (PAC) terminates a complete thought. Moderate closure (IAC, plagal) ends a phrase while inviting continuation. Open endings (half cadence) sustain forward momentum and create expectation. Redirections (deceptive cadence) extend or surprise. In a period, the antecedent typically ends with a half cadence (open question) and the consequent with a PAC (definitive answer). Every cadence choice shapes the listener's sense of whether a thought is complete, continuing, or questioning.
The key is treating cadences as structural decisions that control formal articulation, not merely as harmonic labels applied after the fact. The same V–I can feel final or provisional depending on where it sits in the formal architecture. Composers who master cadential formulas are controlling the listener's experience of arrival and continuation — the punctuation that makes a longer piece legible.