Knowledge for Using Non-Diatonic Chords / Music Theory Lesson

Author: sleepfreaks

Preparation to Understand Non-Diatonic Chords

This time, in conjunction to our knowledge on major and minor (3 types) keys, we will take a look at 1 way to use non-diatonic chords.

Please check out the image below first:

スクリーンショット_2017_05_01_9_44

Lets try analyzing this.

スクリーンショット_2017_05_01_9_44_png

As we can see, we have a chord that isn’t a diatonic chord.

Major_Diatonic_Triad-1-e1477647153571_jpg__1472×540_

Major_Diatonic_Tetrad-1-e1477647954304_jpg__1480×551__と_伊藤講師による音楽理論のための音楽_—_Evernote

However, we can understand the III using our knowledge on the 3 minor key types.
We added a melody to this below:

スクリーンショット_2017_05_01_12_34

スクリーンショット_2017_05_01_11_56

In this case the melody doesn’t have muddy avoid note sounds so using just diatonic chords would work as well.

The example below uses the same melody with only diatonic chords.

スクリーンショット_2017_05_01_9_51

The feel is very different even when using the same melody.
Though the Em→Am isn’t bad, the E→Am sounds nostalgic, and the D→G has a different sound as well.

As seen, there are various chords to choose from when adding a melody to chords.
Try listening to both examples with this in mind.

The previously analyzed songs「Fly Me to the Moon (In Other Words)」「Les Feuilles Mortes」

スクリーンショット_2016_05_11_3_31_jpg

スクリーンショット_2017_03_06_5_21_png_と_第56回 メロディックマイナー・スケール②とノン・ダイアトニックコードの存在②_—_Evernote

Now that we know the minor II-V-I,
we can see how the III / III7 is built into the major key.

How about the other parts:

img_jpg

Lets focus on the areas circled in black and check the diatonic chord chart.

C_diatonic4-768x131

This chart doesn’t have this chord, and isn’t the V of the relative minor key or part of the II-V-I progression.
Lets take a look at the chord progression before and after it.

スクリーンショット_2017_05_01_9_44_png

If we look at the the “I” next to the mystery chord, we can see that it is the V→I of that key.

  • Key=F
    C7→Fmaj7
    V7→Imaj7

ダイアトニックコードのディグリーネーム置き換え(4和音・メジャー編)/音楽理論講座

  • Key=G
    D→G
    V→I

ダイアトニックコードをローマ数字に置き換えて覚える(ディグリーネーム)/音楽理論講座

As seen, the area circled in black contain the leading tone of the key and function as a “V→I” progression to the chord that follows.

Use this knowledge to help understand chords that may have seemed out of place when analysing music.
You may make some new realisations.

Of course, not all chords will fall into these categories.
Next time we will take a deeper look at non-diatonic chords.


Article Writer: Kazuma Itoh

講師 伊藤
After moving to the USA at 18 years of age with a scholarship from Berklee, he completed a 4 year study focused on song writing and arranging there.
Using this knowledge, he works across a variety of fields from pop music, film music, and more.

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