In a major scale, I understand why the I IV V are the most popular chords mainly due to their diatonic functions and they also harmonize the entirety of the scale as they are the primary triads.

I was watching a clip of Ed Sheeran and he was saying "The whole industry... four chords!" and he was referring to the I - V - vi - IV progression.

Which got me thinking about the vi chord. I also recalled a study I read a while back where they did frequency analysis of chords and found that the top chords are I IV V vi. In C major (the key that all the songs were transposed to) the most popular chords were C F G am.

So I was wondering what it is about the vi chord that sets it apart from other minor chords in the major key such as the ii and iii? My current theory is that it's because the vi is the relative minor so maybe there's a tendency to want to go to that.

Please note that this question is solely about this vi chord and mainly in regards to pop music. I understand why the I IV and V are popular it's just the vi that I'm asking about.

  • 1
    I’m not sure if this really admits to one answer. One thing that distinguishes the vi chord from the ii and iii chords is the vi contains the tonic for the key as its third, and it has two notes of the IV chord in it. – Todd Wilcox Apr 8 '19 at 3:03
  • Huh, you'd think ii would be more popular--jazz music spams it all over. – Dekkadeci Apr 8 '19 at 6:18
  • Also, maybe the vi–IV–V–I chord progression has a runaway effect and positive feedback loop on its own popularity. As stereotypical as it is and as many compilations of songs that use this chord progression have been made, I don't think people have ever stopped using it, and I doubt they ever will. – Dekkadeci Apr 8 '19 at 6:26
  • I'd have put the order as I V IV vi - surely V gets more use than IV? – Tim Apr 8 '19 at 7:04
  • There's not a huge choice left. ii often gets substituted for IV, and iii used instead of V, leaving viio, which doesn't get the airing it deserves! – Tim Apr 8 '19 at 7:16

In my experience with both classical and popular musics, there are a few possible reasons:

  • The vi (or VI) chord includes the tonic pitch. Furthermore, it does so in an environment that is the modal opposite of tonic: in a major key, vi is minor, and in a minor key, VI is major. (Obviously this can change with mode mixture, but you get the point.)
  • Similar to the above point, vi can function as a tonic substitute. This is especially common in the deceptive progression V–vi, but it can happen elsewhere, as well. In fact, this sense of tonic substitute is so strong that some excerpts in popular music never states the tonic chord (!). Instead, the chorus just plays IV–V–vi / IV–V–vi again and again such that we get a sense of tonic without ever hearing the actual tonic triad. I have a few examples of this stored in my brain somewhere, but they're not coming to me at the moment; I'll be sure to edit this if any examples come back to me.
  • But perhaps most importantly, vi has two common tones with the tonic chord. As such, the I–vi progression is incredibly smooth: the only difference is a single whole step. And this is ultimately the reason, in my opinion, that the four most common chords are I, vi, IV, and V: the I–vi progression shares two common tones, and vi–IV also shares two common tones. This makes the I–vi–IV progression one of the smoothest progressions available in tonal music; just throw a V–I at the end and you've got yourself a (opinion deleted) pop song.
| improve this answer | |
  • 1
    This feels a bit like stating the obvious. Why should the OP be convinced that these simple facts are a reason, or the reason, for the popularity of the vi chord? – piiperi Reinstate Monica Apr 8 '19 at 5:54
  • 2
    It's music theory; we try to explain why things in music happen, no? (And these facts may not be "obvious" or "simple" to everyone.) – Richard Apr 8 '19 at 5:55
  • 1
    Seeing that the I and vi triads have two common tones is hugely more obvious than the logical jump to believing that that's the reason why the vi chord is so popular. Or that because it's smooth ... the really interesting non-obvious explanation, IMO, would be showing or explaining what makes the smoothness popular and desireable in pop music. :) – piiperi Reinstate Monica Apr 8 '19 at 6:06
  • 1
    If all a piece did was spam IV–V–vi, I'd probably reinterpret it as (b)VI–(b)VII–i and therefore figure it has a tonic chord. For example, I'd think that a piece that uses only the F–G–Am chord progression would be in A minor. – Dekkadeci Apr 8 '19 at 6:23
  • 1
    Similarly for the bullet about tonic substitutes. What's the motivation, why would someone want to hear a tonic substitute in pop music? Something wrong with using or hearing the tonic? What added benefit does a substitute give? I think your answer would be more complete if the theory-land things were more anchored to the human motivation land. – piiperi Reinstate Monica Apr 8 '19 at 6:33