Quality Change

From chapter II, you’ll learn more chords other than six prime chords.

But you may plan to finish studying at chapter I. Then, All that you get is just these six chords…which is a bit insipid. So I pick up some useful chords from later chapters and briefly introduce them.

In later chapters I’ll explain them again in detail, including by what logic they’re “permitted” to use in traditional theory. But, you know, actually you don’t need to ask for any permission from theory! What matters is how to utilize it in practice.

1. Chord Quality

Chord types like major/minor are properly termed Chord Qualities. When chord qualities change, the output sounds also change, so do the moods they produce. If you lower the 3^rd of a major chord, you’ll get a minor chord. Conversely, lowering the 3^rd of a minor chord results in a major chord.

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And this could be where to start exploring—Generating new chords by exchanging major/minor quality!

Quality Change

By exchanging major/minor chord qualities of the prime chords, you’ll get six new chords, which can serve as tasty “spice” to enrich music.

Lower 3^rd in major, raise 3^rd in minor. As a result, accidentals are added in score. Changing chord quality is simply termed Quality Change¹. These are the typical non-prime chords you should master first.

In Classical theory, by the way, changing a pitch by an accidental is called Alteration. Therefore those new chords are called Altered Chords.

2. New Quality, New Sound

Now, let’s listen to examples!

VI : Unexpected Lightness

VI_m originally is minor chord with T function, the dark terminal of chord progressions. So converting it to major naturally gives an impression like a sad ending is changed to a happy one, like you see the bright side of life.

Especially, using VI at the end of a progression produces a typical mood of hopeful ending:

IVVVI_mIII_mIVVVI

First showing VI_m and then exchanging it with VI is a good strategy to form a clear contrast between dark and light.

Modest Use

Or you can insert this chord in a more subtle way.

II_mVIVI_m

This is just another progression with VI_m. If you convert the quality…

II_mVIVI

Can you hear the difference? It’s really subtle but with VI_m lightened, the sum of “happy” feel gets greater.

Song Example

“Spectrum” by Zedd starts with A♭-B♭-Cm progression in Cm key, meaning IV–V–VI_m. After that IV–V progression comes again, but this time followed by VI, the quality-changed version of VIm (at “drama”).
If you cannot clearly see it, check the main melody line, which goes like G-F-E♮-C-E♭. The E♮ definitely indicates the quality change from C minor to C major.
As this progression is used throughout the song, the same is true to the chorus part. It starts with 4-5-6, but at “never let you go”, IV–V–VI appears.

The chord changes might be more noticeable in the acoustic piano version compared to the EDM style with synth pads:

By converting VIm to a major chord, the message of “never let you go” stands out more prominently and conveys a sense of hopefulness. EDM artists often prefer simple chords, but Zedd takes a different approach. By changing chord qualities, he expands the palette of chords and creates more dramatic stories of music.

III : Emotional Surge

On the other hand, III chord, the majorized version of III_m, does not bring much sense of brightness. Instead, the D functionality seems to be enhanced; it has the power to approach the emotional peak of a chord progression.

III_m is known for its “dual-faced” character (D or T). But when majorized, it seems that the similarity to I is lost and it starts to dedicate itself to its main job—the “uppermate” of VI_m.

IVIII_mVI_mII_m

This is an unaltered one. III_m is dark and deep, but it feels like something is not enough……

IVIIIVI_mII_m

This is the majorized version! The difference is again subtle, but raised 3^rd creates a strong sense of reaching a climax of emotion.

This emotional feel is especially fit for ballads. III is much often used in Classical music, Jazz, R&B and so on.

Song Example

Billie Eilish’s “everything i wanted” is a good example. It starts with the loop of a 4-5-3-4 progression. Here, the III_m chord functions in a truly subtle manner, serving as an ambiguous element that is neither clearly D nor T.
This progression continues into the chorus (1:29-), but a change finally occurs in the third round—The III_m shifts to III! Here, the melody also reaches its peak with the phrase “the way that you”, creating a synergistic effect that clearly marks this moment as the climax of the chorus.

II : Versatile Actor

II can act as many roles depending on contexts. It can simply brighten the mood, or it can bring some European ethnic music feel etc.

Lighten the Mood

III_mIVI

This is an unaltered version. The progression sounds merry as a whole but II_m is still dark in terms of its sonority. So try converting its quality…

IIIIVI

II, getting lightened, brings sunnier and more spacious atmosphere! Also, any quality change inevitably involves alteration of a note so it brings a new “color” to a song anyway. As the effect of converting II_m is not so big, you can casually interchange II_m and II.

Modest Use in Minor Key

Next, how about using II in minor key environment?

VI_mVIIII

This is a case in hard rock style. The overall mood governed by VI_m, you may not feel II so merry as the previous example. Another difference is that the guitar solo does not play altered note at all, by which the deviation from the original key environment is restrained. This means that you can control the effect of quality change by adjusting how obviously an altered note is played.

Song Example

“Walk On” by U2 is a perfect example. The song is in D major key, and the intro part starts with D-A-G-Em, that is, a 1-5-4-2 progression, which becomes the basic progression through the song.
However, at the end of the second round, just before transitioning into the verse part, E is used instead of Em. This is a quality change from II_m to II.
After that, II is consistently used at the end of each part, such as at the end of the verse, the chorus, and the bridge. Here, the non-prime chord firstly creates a sense of anticipation for the transition to the next part. Additionally, using a major chord instead of a minor chord for the important supportive message (e.g. “Be strong”, “Stay safe tonight”) should help to reinforce a positive feeling!

IVm : Pathos or Nostalgia

Theoretically, converting major into minor makes a mood darker. But IV_m brings something more than mere darkness or sadness; some sort of nostalgia.

IIV_mIIV_mI

Such a calm progression is fit for verse part. Compared with normal IIV loops, iterating major/minor qualities makes a more colorized mood.

IVIV_mI

Connecting IV to IV_m is a standard pattern to emphasize the effect of conversion, typically usable for ballads.

Song Example

Radiohead’s “No Surprises” is a typical example of utilizing the melancholy of IV_m. Its intro is a simple repetition of I and IV_m.

Vm : Twisted Dominant

I bet you’ve already got the idea that V is a very important piece in constructing a chord progression. It’s the one and only chord that can reach the definite peak of a progression. So changing its quality is less frequent AFAIK.

VI_mVIVIV_m

This is an unaltered version. The progression is plain, seems not much interesting. Now convert the quality of V into minor, to bring some “surprise”.

VI_mV_mIVIV_m

Again the difference is not big, but some “twisted” feel is added to the sound. In this case it doesn’t produce much “sadness” or “darkness” which minor chords typically have.

Im : The Total Reversal

Changing I to I_m means the total reversal of major/minor key so it is the most advanced technique, even less frequently used. For now I withhold explanation until Chapter II.