What does the vi chord do, and how does it create the deceptive resolution?
Topic 5.2 The vi (VI) Chord: use the submediant as a tonic substitute and as the goal of a deceptive cadence, and part-write V to vi correctly.
A focused answer to AP Music Theory Topic 5.2, covering the submediant vi (VI) as a tonic substitute, its role in the deceptive cadence V to vi, the special doubling needed to avoid parallels in V to vi, and its use to extend a phrase, with a worked deceptive resolution.
Reviewed by: AI editorial process; not yet individually human-reviewed
Have a quick question? Jump to the Q&A page
Jump to a section
What this topic is asking
The College Board (Topic 5.2) wants you to use the submediant vi (VI in minor) as a tonic substitute and as the goal of a deceptive cadence (V to vi), and to part-write V to vi correctly, including the special doubling needed to avoid parallels.
The submediant as a tonic substitute
Because it shares so much with the tonic, vi can momentarily satisfy the dominant's pull while keeping the music open, since vi is not a true point of rest.
The deceptive cadence
The deceptive cadence is a favorite way to extend a phrase: a composer builds to the expected cadence, then sidesteps to vi, and writes more music before finally reaching a real authentic cadence.
Why vi extends rather than ends
The central idea is that vi gives the feeling of resolution without the finality, which makes it a perfect tool for prolonging music. Because it shares the tonic's lower two tones, the ear accepts vi as a soft landing when the dominant resolves to it, but because its root is not the tonic, the music still feels unfinished and wants to move on. Composers exploit this to avoid ending too soon: the deceptive cadence resolves the dominant's tension just enough to be satisfying, then leaves the door open for a fresh approach to the real cadence. The doubling rule, doubling the third of vi, is the practical consequence of the leading tone rising to scale degree 1, which is the third of vi: doubling that note lets the voices resolve cleanly, whereas doubling the root would force parallels. Understanding vi this way lets you both analyze phrase extensions and write convincing deceptive cadences.
Part-writing V to vi
To write a deceptive cadence, spell V and vi, resolve the leading tone up by step to scale degree 1, move the bass up a step from degree 5 to degree 6, and double the third of vi so the remaining voices fill the chord without parallels.
Try this
Q1. Which two scale degrees does the vi chord share with the tonic triad? [1 point]
- Cue. Scale degrees 1 and 3; this overlap is why vi can substitute for the tonic.
Q2. In a root-position deceptive cadence, which tone of vi do you double and why? [2 points]
- Cue. Double the third of vi (scale degree 1), because the leading tone resolves up to it; doubling the root instead would cause parallels.
Exam-style practice questions
Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
AP 2022 (style)1 marksSection I (multiple choice, written). A phrase reaches a strong V and then moves to vi instead of I. What is this progression called? (A) plagal cadence (B) half cadence (C) deceptive cadence (D) perfect authentic cadenceShow worked answer →
The correct answer is (C) deceptive cadence.
A deceptive cadence is V to vi: the dominant sets up an expected resolution to the tonic, but the submediant (vi) appears instead, surprising the listener and usually extending the phrase rather than ending it.
(A) plagal is IV to I. (B) a half cadence ends on V. (D) a PAC is V to I in root position with the tonic in the soprano. The trap is hearing a strong dominant and assuming the next chord is the tonic; the deceptive cadence substitutes vi, which shares two notes with I.
AP 2023 (style)3 marksSection II (free response, part-writing). In C major, part-write a deceptive cadence V to vi, state which tone of vi you double, and explain why that doubling avoids parallel octaves.Show worked answer →
A 3-point part-writing question.
(1 point) Spell the chords: V is G, B, D; vi is A, C, E. In V to vi the bass moves up a step, G to A.
(1 point) The leading tone B (in V) rises to C (in vi), as a leading tone should. To complete vi and avoid parallels, double the third of vi (C, which is scale degree 1), giving A, C (doubled), E.
(1 point) Doubling the third of vi works because the leading tone resolves up to that doubled tone naturally; if you instead moved both upper voices in parallel you would risk parallel fifths or octaves between the bass and an upper voice. The standard solution is to double the third of vi in a root-position deceptive cadence.
Markers reward the leading tone rising to scale degree 1, doubling the third of vi, and explaining that this doubling lets the voices resolve without parallels.
Related dot points
- Topic 4.3 Harmonic Progression, Functional Harmony, and Cadences: explain tonic, predominant and dominant function, the normal direction of progressions, and the four cadence types.
A focused answer to AP Music Theory Topic 4.3, covering functional harmony (tonic, predominant, dominant), the normal flow tonic to predominant to dominant to tonic, and the four cadences (perfect authentic, imperfect authentic, half, plagal, with the deceptive cadence), with a worked cadence analysis.
- Topic 5.1 Adding Predominant Function IV (iv) and ii (ii diminished): use the subdominant and supertonic chords to prepare the dominant and part-write them smoothly.
A focused answer to AP Music Theory Topic 5.1, covering predominant function, the IV (iv) and ii (ii diminished) chords, how they lead to the dominant, the use of ii6 and first-inversion predominants, and smooth part-writing, with a worked predominant progression.
- Topic 5.4 The iii (III) Chord: use the mediant as a connecting chord between I and IV (or vi) and part-write it within a diatonic progression.
A focused answer to AP Music Theory Topic 5.4, covering the mediant iii (III in minor), its weak and ambiguous function, its common use to harmonise a descending scale degree 7 to 6 in the soprano or to connect I to vi or IV, and smooth part-writing, with a worked progression.
- Topic 5.5 Cadences and Predominant Function: build complete cadential progressions with predominants and harmonise a given melody so it cadences correctly.
A focused answer to AP Music Theory Topic 5.5, covering full cadential progressions that include a predominant (such as I, IV or ii, V, I), how the predominant strengthens the approach to the cadence, and how to harmonise a given melody so the cadence lands correctly, with a worked harmonisation.
- Topic 4.2 SATB Voice Leading: apply the rules of range, spacing, doubling, smooth motion and tendency-tone resolution when writing four-part harmony.
A focused answer to AP Music Theory Topic 4.2, covering the four-voice ranges, the spacing rule (no more than an octave between adjacent upper voices), doubling guidelines, the ban on parallels and voice crossing, and resolving the leading tone and tendency tones, with a worked voicing.
Sources & how we know this
- AP Music Theory Course and Exam Description — College Board (2024)