In this lesson, we'll look at another very common diatonic chord progression: the I-vi-IV-V chord progression (“One-Six-Four-Five”).
This progression is common in most styles, especially rock, pop, R&B, and many ballads. You'll find it either as the main progression throughout a tune, a section of a larger progression, or a turnaround.
The I-vi-IV-V Chord Progression
The I-vi-IV-V chord progression is really just a variation of the I-vi-ii-V chord progression we looked at in the last lesson. Notice it is only different by a single chord. The ii chord has been replaced by its happier, major cousin—the IV chord.
Having mostly major chords gives the I-vi-IV-V progression a bit more brightness. Since its roots aren't all in fourths, it has a little less symmetry, and it might feel a little less predictable.
In harmony, substitution chords are chords which can be swapped for one another.
Often when two different chords function similarly, they can be substituted (or “subbed”) for one another. Functioning similarly means they produce similar musical results. A subbed chord connects from one place to the next, and creates tension or resolution, similar to the original chord.
What makes them function similarly? The two similar chords will have several important notes in common. Those in-common notes will connect from one chord to the next in the same way.
For example, the IV chord is a very common substitution chord for the ii chord. Therefore, in the key of G the IV chord (C major) can be substituted for the ii chord (A minor).
The C major chord has the notes C, E, and G. The A minor chord has the notes A, C, and E. Two of the three notes—C and E—are the same, and these notes will likely connect to the next chord in the same way.
If the idea of substitution chords doesn't make sense to you yet, don't worry. We will revisit this idea many times in the future.
The I-vi-IV-V Arpeggios
By now, you should know the drill. Practice the arpeggios to help get the sound of this progression in your mind and under your fingers.
Here are the four chords of this progression in the key of G:
The I-vi-IV-V Progression in Every Key
Here are the chords to the I-vi-IV-V progression in every key:
Example I-vi-IV-V Songs and Exercises
I've made a few example basslines over the I-vi-IV-V progression. Play through them and pay attention to the application of chord tones in each bassline.
There are many, many songs using the I-vi-IV-V progression. See the songs on the songs tab and play a few of them.