Four Note Chords - Dominant Seventh Edition / Music Theory Lesson

The Chord with Tension – “Dominant Seventh”

This time, we will be looking at the particularly “tense” sounding
dominant seventh chord.

This “tension” may be related to the tritone that our last article took a look at.

This dominant 7th chord can also easily be made by understanding the 3 note chords from our previous articles.

Lets hear how it sounds first.
The chord will play after the individual notes are played.

Dominant 7th chords are often depicted as the following:

In general this way of displaying it works in most cases.

C Dominant 7th = C7

D Dominant 7th = D7

Calling a chord the “~ dominant seventh chord” is a little long,
so it is often shortened down to “~ seven”, “~ seventh”, or “~ seventh chord”.

The Basic Shape of the Dominant 7th Chord

Lets take a look at a basic C7 chord on notation and the piano roll.

Did you realize something here?

That’s right. Like the C major 7th chord, it contains the C major chord within it.
Once again, you already have the foundation of knowledge for this chord.

Because both the dominant 7th and major 7th chords contain the major triad,
lets compare the two chords.

Cmaj7 will play first followed by C7.

By lowering the M7th of the major 7th chord by a half-step, and turning it into a m7th,
you can create the basic shape of a dominant 7th chord.

Therefore, dominant 7th chords are:

In intervals: R M3rd P5th m7th

In scale degree: 1 3 5 b7

How to Easily Create Dominant 7th Chords

Though the 7th note seems far away, we can utilize the “opposite approach” to
quickly create a G7 chords.

Once we have a G major chord,
we can add a note a whole-step beneath the root to add a m7th and create a dominant 7th chord.

The Relationship Between Dominant 7ths and Tritones

The G7 chord is fairyly simple, made up only of the white keys G B D F.
However, it has a worried and tense feeling to it.

This touches back on info from our last article,
but this dominant 7th chord in fact contains the tritone interval.

In our previous article we mentioned a moment when the “tritone moves to a certain sound”
but lets see what we mean by this.

With B→C and F→E, both notes move by a half-step.
By playing a certain chord after a dominant 7th, we can get a certain effect.
You may have already made this connection.

After learning the minor 7th flat 5 chord in our next article,
we will move on to how we can utilize the chords we learned,
so stay tuned!

Article Writer: Kazuma Itoh

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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