Solar Harmony and the Chord Ladder
Although there are seven diatonic chords available, there is no steadfast rule about which one to use and why. No one can tell you how to compose! However, it is possible to study the evolution of music and see some trends that are worth investigating, even if you choose to go off in your own direction and look at chords differently.
Earlier, this book touched briefly on solar harmony by stating that the tonic chord is the most important chord in any key and that the other chords circle around it. Now you'll discover what this actually means.
In tonal music, the tonic chord serves two roles: the start and the end. It begins phrases and ends them. The term gravity is hard to explain on paper, but you know it when you drop something on the floor. With musical gravity, when you write tonal music, progressions tend to gravitate back to the tonic chord each time. Because phrases tend to want to come to rest and end there, composers worked their hardest to prolong the inevitable moment of coming back to the strong tonic. Eventually, tonality in classical music fell out of favor because too many composers found the strong tonic chord increasingly difficult to use in new ways. Amazingly enough, to this day, tonal music thrives, and harmonic gravity gives music its power and beauty.
FIGURE 9.4 gives a good example of tonal gravity. Listen or play this example on an instrument right now.
FIGURE 9.4 An Unfinished Example
Isn't that brutal? Doesn't that F# want to pull up to the G more than you can express? Why does it do that? No one knows for sure, but you have hit on exactly what makes melodies and chord progressions move: the inevitable pull back to the tonic note. You saw it with a simple melody; it appears in FIGURE 9.5 with a single chord voicing.
FIGURE 9.5 More Musical Torture
Why is it that this chord refuses to sit still? This chord, a G7 chord, is diatonic to the key of C major. It is the V chord, or dominant chord. In this example, it is a seventh chord. So, why does this chord want to go someplace else? Harmonic gravity. It's not the tonic chord, it's actually one step removed from it; it's the closest chord to tonic (more on that soon), and it wants to go to tonic. So, here's how it resolves in FIGURE 9.6.
FIGURE 9.6 Resolution!
You came back to the tonic, back to the center of the musical system, and finally you have resolution. Tension and release are what make this whole game work.
You've heard about two chords: I and V. Now, look at the rest of the chords and how they align with the tonic chord by looking at the chord ladder.
The Chord Ladder
The chord ladder is a neat little device that shows the relationships among all the diatonic chords in a key. Take a look at the ladder in FIGURE 9.7, and then you'll learn more about exactly what it's showing you.
FIGURE 9.7 The Almighty Chord Ladder
It's a ladder with chords on it. Basically, this ladder is a reference to the “harmonic” gravity mentioned earlier. All the chords in some way fall to the I chord at the end.
There are a few things to observe. First, notice that there are different steps on the ladder, and occasionally, there is more than one chord on those steps.
When two chords occupy the same step on a chord ladder, it means that the chords can substitute for each other. Before you go any further, you need to know what makes a chord substitute for another chord.
On the first step of the chord ladder is the I (tonic) chord and a very small vi chord on the final step. They occupy the same step because both chords can substitute for each other. They share common tones; more specifically, they share two-thirds of their tones. In the key of C major, I and vi share the following tones (see figure 9.8).
FIGURE 9.8 Shared Tones
On every step of the ladder, when you find two chords occupying the same place, it's because they can substitute for each other due to sharing of tones.
Ladder of Fifths
Remember the circle of fifths, here's a ladder of fifths. Many, many chord progressions are based on movements of fifths. So, now look at the chord ladder without the extra chords and view it as strictly fifth-based movements from the tonic chord up (see figure 9.9).
FIGURE 9.9 The Chord Ladder in Fifths
You end up with a progression of iii, vi, ii, V, I. Look at that for piano and guitar in FIGURE 9.10.
FIGURE 9.10 Full Fifths Progressions
This example sounds fine, doesn't it? Sure it does!
Now start to throw in some of the substitute chords, as in FIGURE 9.11. See what replacing the ii with a IV and the V with a vii° chord look and sound like.
You get a nice-sounding progression. Unfortunately, no matter how you slice any of these progressions and no matter how crafty you are, when you get to the V (or its substitute, the vii° chord), you pull back to I. Or do you? Remember the small vi chord next to I on the chord ladder.
FIGURE 9.11 Use Some Substitute Chords
The small vi chord is there as a deceptive resolution to the I chord. Essentially, you break the pattern that V has to resolve to I by allowing V to resolve to vi. It's called a deceptive cadence.
Here's what so neat about the progression: Just when you think you're going to cadence back to I and essentially end the progression, the music pulls a fake out and gives you a vi chord. It prolongs the progression as it sets you back a bunch of steps on the ladder, giving you more time to keep the musical phrase alive and continue the progression.
If you wondered why the vi chord was in very small print, that's because while it substitutes for the tonic chord, it's more of a transport, magically linking you back to the real vi chord on the chord ladder. Maybe the ladder should have looked like FIGURE 9.12.
FIGURE 9.12 Chord Ladder Warp!
The chord ladder does not dictate what you should or should not use when writing music. It simply presents a number of choices that will work well together. The ladder illustrates how chords typically progress in diatonic situations. Feel free to use it as a starting point and go your own way from there.
ETUDE 9.1 Etude One
Circle the primary chords and name the chord progression with Roman numerals
ETUDE 9.2 Etude Two
Circle the secondary chords and name the chord progression with Roman numerals
ETUDE 9.3 Etude Three
Using the chord ladder, find a substitute chord for the ii chord and insert it in the progression below
ETUDE 9.4 Etude Four
Circle the chord that breaks the progression from moving completely in fifths
ETUDE 9.5 Etude Five
Circle the deceptive resolution in the following chord progression