Why does V7 resolve so well to VI∆7?

Question

One progression I come across often (in tonicizations or modulations) is V7 to VI∆7. For example: G7 to A∆7.

In playing with it, I notice that the V chord can be in many different forms, including dominant and sus chords. The VI seems to be more fussy: only VI chords containing the major seventh seem to work especially well.

Why does this progression work so well?

Example: "Knocks Me Off My Feet" by Stevie Wonder, bar 4 to 5.

Answer 1

"Why does x work?" I've played piano by ear for 35 years and I've never felt a need to ask why something works. I don't understand what that question means. It works for you because you like the things the chord change does? Someone might think it sounds cheezy. (It does, a bit.) All I need is to hear what it sounds like, and look at the pattern that goes on with the notes. Ok, this sounds like this. Then I can apply the pattern in situations where it feels appropriate.

But if you ask, what happens from some perspective in that chord change, it's a much more answerable question. I can think of two things:

• If you expected a I chord, getting VI maj7 is a surprise.
• The VI chord, especially when it's maj7, forces chromatic alterations to the listener's assumptions of what pitches or scale degrees "fit" or are expected to be heard, which I call "harmonic context". The VI chord raises the I degree to #I (or whatever is the appropriate notation), and the maj7 raises the V degree to #V. This can be seen many ways, for example as a change between parallel major/minor. Or you could call it modal interchange between something and something.

To "milk" the same modal interchange phenomenon, and switch between A minor and A major, try this:

Amaj9 G69 F#m9 Fmaj9 (repeat)

it keeps switching scale degrees from sharp to natural and back. If you like the sound of that, then it works for you.

Answer 2

These deceptive motions typically function so well because something about the chord of resolution is a part of the expected chord.

Your question could allow for two chord progressions: in the sample key of C, either G–Amaj7 or G–A♭maj7. We can address both of them.

When we have a G chord in C, we often expect it to move to C. Put another way, we expect it to move to a collection of {C, E, G}. When it moves to Amaj7, we move to a chord with a prominent E in it, thereby realizing some of our expectations while not realizing others. But because at least one pitch here is what we expected, we get a sense that this chord is kind of right, but also very very "wrong."

This explanation is even more clear when moving to A♭maj7. We expect the G chord to move to {C, E, G}, or perhaps even (in minor) {C, E♭, G}. The A♭maj7 chord actually has all three of these pitches—C, E♭, and G—with an added A♭. But because it has all three of our expected pitches, this one is really convincing as a chord of resolution...there's just that one pitch, A♭, that prevents it from sounding complete.

The VI seems to be more fussy: only VI chords containing the major seventh seem to work especially well.

I admit I don't have an answer for this one, and perhaps because my experience doesn't align with yours; I've found that these VI triads are perfectly good deceptive goal points, and that the seventh isn't necessary. But clearly our results may vary!