57. Knowledge to Prepare for Non-Diatonic Chords

First, take a look at the following.

Let's actually analyze it.

As you can see, a chord that did not exist among the diatonic chords has appeared.

However, you can understand the III part now that you have learned the three types of minor.
I added the following melody to it.

In this case, the melody does not sound muddy as an avoid note, so it would also work with diatonic chords alone.

Below is the same melody using only diatonic chords.

Even with the same melody, the impression is very different.
Em -> Am isn't bad, but E -> Am creates a bittersweet mood, and D -> G also gives a different impression.
As you can see, when putting chords to a melody, there are many chord options.
Try consciously listening to and comparing the two songs.

• "Fly Me to the Moon (In Other Words)" and "Les Feuilles Mortes," which we used in earlier lessons

Now that you have learned the minor II-V-I, you can see how III and III7, viewed in the major key, were incorporated into the flow.

But what about the other parts?

Look at the diatonic chord table while paying attention to the parts circled in black.

That chord is not in this table, nor does it appear in the V or the II-V-I (two-five-one) flow of the relative minor key.
Now let's focus on the relationship between the chords before and after, including the chord progression that appeared at the beginning.

If you treat the chord next to the mysterious chord as "I," they all form a "V -> I" relationship in another key.

• Key=F
  C7 -> Fmaj7
  V7 -> Imaj7

• Key=G
  D -> G
  V -> I

In this way, you notice that the parts circled in black all form a "V -> I" relationship that contains the leading tone of that key.
With this way of thinking, take another look at chord progressions you couldn't understand with knowledge of diatonic chords alone.
You are sure to make new discoveries.
Of course, you will also come across chords that do not fit this relationship.

Next time, let's dig deeper into these non-diatonic chords.