We know the chords now, but what order do we play them in; what makes a good song?
Most music in the European and North American traditions follows a predictable pattern of chords. There are a number of ideas as to why this is. But for our purposes, we can say that it's just what sounds pleasing to our collective cultural ear.
The basis of this pattern is the I-IV-V (1-4-5) chord theory.
Conflict and Resolution
Let's go back to our discussion on triads. Here are the 7 triads of the C Major scale:
The chart above shows the Roman numeral for each chord. The Roman numerals allow us to talk about chord relationships without getting into the specifics of what key we are in. The relationship between chords remains the same no matter what key you play in, so Roman numerals are used instead of the actual chord names.
Since C Major (or “I chord”), in the chart above, is the key center, the C Major chord is the one that is stressed throughout a piece of music that is in the key of C. All other chords shall be considered brief departures from that comfortable key center. When you depart from that key center, the listener perceives tension; we are outside the comfort zone. Any chord apart from C Major will produce this affect, but some produce it more strongly.
The vi chord, or A minor (ACE) in this case, is only a slight departure from the I chord, C Major. They share two of the same notes, C and E. As a result, the transition from C Major to A minor, or vice versa, is a very cozy one.
The V chord (G Major) on the other hand shares only one note with the I chord (C Major), the G in this example. The other two notes in the G Major chord are B and D. These two notes are so close to C that they want to “fall” into it. Don't believe me? Play a C Major scale upwards and stop at the B note. Hear that? Your mind wants to hear the C note. It's almost painful to not hear it. Now play the C Major scale again downwards and stop at the D. The same effect: "where's my C? Gimme a C!" Go ahead, play the C. This is why the G Major chord needs to resolve to the C Major, it just sounds right.
If we add the seventh note to the G triad, we get even more tension because the F note in the G7 wants to resolve to the E in the C chord.
Let's look at the IV chord in C Major: F Major, FAC. The chords C Major and F Major both share a C note so no tension there. The F note in the IV chord forms tension with the E of the I chord. And the A in the IV chord wants to resolve to the G in the I chord. So in all, the move from the IV chord to the I is relatively tense. Not as much as V7 to I, but it definitely eases some tension to move from IV to I.
The term for moving toward resolution in a phrase or complete piece of music is called cadence. In practice, cadences give a sense of pause or finality to a section of music. Different chords can be used to create cadence, but most often it is different inversions of the IV or V chord moving towards the I chord that create the cadence.
Some cadences have special names to distinguish them. The move from a V to a I chord, (which is the most common cadence) is called an "authentic cadence." There are different types of authentic cadences based on which inversions of the V or I chord are used. The IV to I chord is called the "plagal cadence" (sometimes referred to as the “church cadence” because of its prominent use in classical church music). A cadence can be created by resolving to the vi chord. This is called a "deceptive cadence" because it is unexpected and creates a sense of confusion to the resolution. There is also a "half cadence," which is a resolution toward the V chord instead of the I chord. This causes a sense of tension and a lack of finality to the cadence. This tension is usually resolved with an authentic cadence in the next phrase.
The succession of chords in a piece of music is called a chord progression, and the I-IV-V chord progression forms the basis of western (Europe and North America) music. Most music concentrates on the I-IV-V in some order or another. Whether it be:
Literally millions of songs have been written using these three chords alone. Occasionally a iii chord or vi is thrown in there, but the I-IV-V pattern definitely predominates. Here’s just a short list proving my point:
So what makes all these songs sound different? Some of them are composed of the same exact chords in the same exact order. True, these songs are usually played in different keys, but that is not what distinguishes them. After all, you can play "Row Your Boat" and "Three Blind Mice" in the same key and they will still sound nothing like each other. Ultimately, you will find that it is the variation in the melodies and the rhythmic structure of the chord progression that makes songs with similar chord progressions unique. These two variables are enough to make hundreds or thousands of songs with the same exact chord progressions sound different.
Modal Chord Changes
So far I've been using examples from the Ionian (Major) mode. If we were to apply the I IV V chord theory to other modes of the scale, we wouldn’t get the same sense of resolution and conflict. Here are the all the modes with their first, fourth, and fifth chords:
You may notice upon playing them that the modal progressions don't sound quite right. That's because the notes do not have the same resolving characteristic that the Ionian 1-4-5 does.
For example, the Aeolian 1-4-5 is vi, ii, iii. In key of C major, that's ACE, DFA, and EGB. When you play the 5-1 resolution (iii-vi), it doesn't have the same finality that an Ionian V-I change does. This is because the G in the E minor chord is a little further away the than the B in a G major chord in Ionian mode. Look:
With the V-I, the B is so close (1 semitone) to the C it wants to fall into it.
With the iii-vi, the G is a whole step away from the A, so there's not the same sense of gravitational pull.
The way we can fix this is by changing the iii chord to a III chord. In this example, an E minor to an E Major. Now the notes are EG#B-ACE. This resolves great. And notice our new scale notes: ABCDEFG#A. That's the A harmonic minor scale. In fact, this resolution issue is the exact reason that the Harmonic minor scale was invented. The natural minor just doesn't have the right combination of conflict and resolve.
Other modes share the same problem with the natural Aeolian mode. But they can also be fixed with the same method. Plus, experimenting with resolving notes could lead to exciting new chord progressions in your composition work.
If you have followed the site up to this point, you can read tab and sheet music, play scales, dyads and chords on the steel guitar. So what can you do with this knowledge? There are a few directions to go from here:
1. you can find sheet music or tab for the steel guitar and play it.
2. you can learn how to make your own musical compositions on the steel guitar.
3. you can learn how to improvise on the steel guitar.
4. you can learn to play other musician’s songs by ear.
The first one is simple enough. Just search out the music. Many fine steel guitarists have music for sale.
The last three topics above are addressed in the next two sections: how to compose and how to improvise.