Major 6th / Minor 6th Chords ① / Music Theory Lesson

Though we had looked primarily at avoid notes in the previous few article,
now we will take a look at adding a “6” to create a “sixth chord”.

This is important information that makes use of our previous knowledge as well.
It will tie into avoid notes in our next article so lets take a look at the chord itself first.

Before doing so, be sure you have the information from the following articles down.
If you’re unsure, use the links below to go back and check up on your knowledge.

• 3. Major Intervals
• 4. Minor/Diminished Intervals
• 7. Minor Scales & Scale Degree
• 9. Major Triad Chords
• 10. Minor Triad Chords

Even among the 4 note chords, the 6th chords are a little unique.

First, lets give a listen to the Major 6th chord’s sound.
After the chord tones are played in order, it will play as a full chord.

Some may hear it as a nostalgic sound, a fancy sound,
a gentle and warm sound, and more.

After hearing the major 7th chord, lets give a listen to the major 6th chord.

Though theres only a 1 note difference, it sounds quite different.

The major 6th chord is often depicted as the following.

You will commonly see just the number “6” being used on the left, such as

• C Major Sixth ＝ C6
• D Major Sixth ＝ D6

(In this series we will write it using this method as well).

Lets take a look at the C6 chord on notation and the piano roll.

It made up mostly using a major triad.

Using our intervals, lets see what this chord is made up of.

We can see that it is a major triad (R/M3rd/P5th(1/3/5)) with a “M6th” added to it.

Lets check the scale degrees of the chord as well.

In conclusion, we can see that the basic form of a major 6th chord uses

• In Intervals: R M3rd P5th M6th
• In Scale Degree: 1 3 5 6

Next, lets take a look at the minor 6th chord.
It will be easy to do so now that we know how to make the major 6th chord.

The minor 6th chord is often depicted as the following:

It is commonly written as “m6”.
“min6” is a common way you may see it as well.

Though it may see like “we just turn the M6th (6) to the m6th (b6)”,
this is not the case.

In fact, it is:

• In Intervals:　R m3rd P5th M6th
• In Scale Degrees: 1 b3 5 6

Because of this, the difference with the major 6th chord is thatthe 3rd becomes flat, meaning the triad contained is a minor instead of major (M6th remains the same).

Lets hear how it sounds as well.

Because the M6th and m3rd are a tritone apart, there may be some of you who felt a sense of tension in this chord.
There are ways to use this chord with the tritone in mind as well.

If you ended up turning the M6th(6) to a m6th(b6)…

it creates a very unnatural sound.
This is because it becomes a half-step away from the P5th(5).
There are ways in which this chord can be used as well, but be sure to keep in mind that it is different from the m6 chord.

Lets have one last look at the major/minor 6th chords.

It’s easy to remember these chords by knowing that you just add a M6th(6) to a major/minor triad.

With this in mind, we will be diving back into avoid notes in our next article.