Moving from Chord Construction of Triads to Four Voices Chords

This Piano Chord construction piano lesson is made for those who wish to go a step further with their harmony studies and to establish the chord theory we've been learning so far.

Here are the new four voice chords we're going to cover:

The dominant seventh chord

The major seventh chord

The minor seventh chord

The half diminished chord

The diminished seventh chord

Click here if you want to start learning about piano chord basics.

Let's fresh our memory for a moment. Until today we learned about the chord construction of three-voice chords (triads). We started to construct a chord from its root note by building above it a third and a fifth in the structure of the scale we're in.

If we add a major third to the root note we create the chord construct of a major chord.
If we add a minor third to the root note we form a chord construction of minor chord.

So far so good.

Next we learned to deal with the fifth note of the chord.
Adding a pure fifth to the chord doesn't change the chord constructure much.. It mixes well with both major and minor thirds, but it doesn't give something new to the identity of the chord.

However, we learned that we can raise the fifth and create the chord structure of a major augmented chord or lower the fifth of a minor chord and make it a diminished chord.

Now I'd like us to go a step further and add a fourth voice over the triads in order to create the chord structure of a seventh chord.

What we're basically going to do is simple. In order to create the chord structure of a triad (three-voice-chord) we took the scale degrees and added the third and the fifth note of each scale degree within the scale structure. Now we're going to take this one step further and add the seventh note and see what happens, like this example of G7.

The Seventh Chord

The story of the seventh chord moves in two different dimensions. The first direction is to define the chord as a clear dominant chord and the other is to add color to the chord. We're going to talk about both aspects here.

Adding the seventh note to the dominant chord (fifth degree)

Earlier in our studies when we learned about the three chords and the truth (Click here to go there) we talked about the dominant chord.

First I told you that the fifth degree is called "The Dominant" since it creates a clear tension that points us toward the tonic. In other words the fifth degree wants to go back home to the first degree. Great! But why? Because of voice leading.

If we take a scale we can divide its notes to two groups, the inside notes and the outside notes. The so called inside notes are static notes. They symbol the rest in the scale and are serving as a skeleTone :). Each outside note in the scale wants to go toward an inside note.

The relationship between these two groups in the scale allows us to create the relationships between the different chords. The more a chord contains outside notes the more it points toward the tonic.

Let's take C major for example. The inside notes of C major scale are the notes that form the tonic chord, the C chord (C,E and G). C functions as the ultimate rest and E and G are relatively static (but it mostly ain't over 'till you reach the home base again) Makes sense, doesn't it? The outside notes usually step down to relieve the tension except for the leading tone which steps up. The outside notes of the C major scale are D, F, A, B. The D note (second note) wants to go to the C (first note) The F note wants (fourth note) to go to the E note. (third note) The A note (sixth note) wants to go to the G note (fifth note) And the B note (leading tone and seventh note of the scale) is leading us back to C, the tonic. It contains the most tension in the scale. Note that both D and B want to go back to the tonic.

Now let's go back to the chord construction of a dominant chord. The fifth degree of C major, G major contains these notes G, B, D, . two outside notes and one inside note.

G is an inside note and therefore it stays static.

B, the third note of G major is the leading tone of C major and is clearly taking us back to C (The first note of the scale).

D is the second note of C major and as an outside note it wants to go to E in this case (I showed you before that D wants to go to C, but it can also move to another inside note to get a relative rest and not the ultimate one, as it would be with the C tone).

We can now see how G major leads us to C major. But that wasn't good enough for most composers. They wanted to improve the chord construction of the dominant chord in a way that allows no room to doubt about its function. A G chord can be played in many scales, so how can we define, purely, the ultimate dominant of C major?

We add the seventh note to the chord construction, which increases the tension even more toward the tonic chord.

F is the seventh in a G major Chord. (G is the fifth degree of C major scale. What you have to do is step up seven notes in C major starting from G.

F is the fourth note of C major scale and as I've shown you above, it is an outside note wanting to go to the third and here it is, our new-born baby. Your reliable dominant chord will always take you back to the tonic chord C major.

If we check the intervals of the chord we will see that we've added a minor third above the fifth note.

Here's a free piano chord chart of all twelve dominant chords that will help you find your way on the piano.

Now that we've really learned to know the chord construction of the dominant seven chord here's once again a free piano chord chart of the I-V7-I in all twelve major scales. Pay attention to the voice leading in this chord chart.

Adding the major seventh to the triads of the tonic chord (first degree) and subdominant chord (fourth scale degree)

So far we've added a seventh note to the fifth degree but now I'd like to show you what happens when we add a seventh chord to all other triads based upon the different scale degrees.

Let's start with the tonic. The tonic in C major is a C major chord (C, E, G). When we count seven notes from C (C, D, E, F, G, A, B) we add the seventh note B.

Note that B is a half tone under the upper tonic C While F the seventh note of G major seven is a whole step under the upper tonic G.

The seventh note of the C major chord in C major scale is the major seventh. If we look at the intervals we will see that we add a major third over the fifth note of the chord.

The major seventh gives the chord a wide open sound deriving from the presence of two major thirds in the chord. In this case it serves as a color provider.

Same goes for the subdominant chord who gets the major seventh as well (Try to find it yourself as an excersize).

Here's a free piano chord chart to make sure you get this right.

Adding the seventh note to the triads of the supertonic (second degree), mediant (third scale degree) and submediant (sixth degrees)

If we add a seventh note to the triad of the second degree we get a D minor seventh chord (By counting seven notes from D in the frame of C major: D, E, F, G, A, B, C, D).

The seventh note of D minor is a small third above the fifth note.

The small third is being added to the mediant triad and the submediant triad as well.

Here's a free piano chord chart with all minor seven chord to assist you locating them on the piano easily.

Remember what we've learned about the II-V7-I chord progression?

If you play the same chord progression with adding a seventh note to the second degree you'll find the seventh chord is increasing the feeling of suspension before the dominant seven.

When the II7-V7-I is being played we play the II7 chord with the third note or the seventh as the lowest note. We'll discuss this in our next piano chord lesson.

For now here's a free piano chord chart of II7-V7- in all major scales.

Adding the seventh note to the leading tone chord (seventh degree)

In this case the seventh chord gives a color to the chord and instead of increasing the tension.

Guess what? I've made you another free printable piano chord chart of all twelve half diminished chords.

But what happens if we lower the seventh note in half a tone? Then we get a chord made of three small thirds one on top of the other. Such a chord is enormously stressful in the environment of the major chord (for example Bo in C major).

Here's the final piano chord chart of this page with all twelve diminished seven chords.

Let me refresh your memory and tell you that the seventh triad functions as a substitute for the dominant chord. So if we add the lowered seventh to it we increase the tension enormously toward the tonic (first degree) just like we did with the dominant seventh (fifth degree).

Next in our piano chords lesson I'd like to deal with the sus chords which sustain the seventh chords. Click here to have a look at the Sus Chords.