We continue with the chords, the base of harmony in music. Today we will discuss chord functions and chord progressions.
6. Chord Functions, Chord Progressions
It is time to learn about chord functions – the roles they play in the entire musical piece. With this knowledge you’ll be able to learn about chord progressions. By now you should know that we use roman numerals for each of the seven chords, build upon seven degrees of the scale. For example, we have chords I, ii, iii, IV, V, vi vii in major scales. The uppercase roman numerals represent major chords, and lowercase roman numerals represent minor chords.
There are seven chords in a major and minor scale, because we build each chord upon a single degree of a scale – a single note. And there are seven notes in a typical minor and major scale.
An augmented chord is usually marked with a + sign, and a diminished chord is usually represented by a circle next to a numeral. That said, there are rarely any augmented chords in normal scales.
Figure 6.1 shows the chords in a C Major scale.
From the left, we have:
- I – C Major
- ii – D Minor
- iii – E Minor
- IV – F Major
- V – G Major
- vi – A Minor
- vii – B Diminished
Minor scales have the same degrees (i, II, III and so on…), and in any scale we start with a roman numeral I – that represents the tonic function of a chord. In every scale, no matter if major or minor, and no matter what chromatic note this scale starts with, we start with I and end up on VII, and every single chord on a particular degree has the same function. For example, chord I in scale C Major is a tonic, and chord I in A Minor is also a tonic. The numeral and function and the name of the chord remains the same. Only the notes change. Every chord built on a fifth degree of a scale is a V – Dominant chord. Every chord built on a second degree of a scale is a II – Supertonic chord.
Each of the seven chords has a name:
- I – Tonic
- II – Supertonic
- III – Mediant
- IV – Subdominant
- V – Dominant
- VI – Submediant
- VII – Leading tone (or subtonic in minor scales)
And each of these chords has a “function” – it plays a specific role in a chord progressions, the underlying structure in music. This is where we start talking about harmony.
We have three main chords – I, IV and V – the tonic, subdominant and dominant chords. These three chords, together, contain all the notes of a scale. For example, in C Major a tonic is made of C, E, G; dominant is G, B, D; subdominant is F, A, C; in total, we have all the notes of the C Major scale. With these three chords, we can harmonize any kind of melody written in C Major. Harmonization is a process of adding chords to a melody – the chords should fit the melody, this is a basic rule.
We have four other chords: II, III, VI and VII. Each of these chords finds its place in a chord progression. A chord progression is a… well, progression of chords, one after another. Each chord in a chord progression can lead to a couple of other chords and the rules that says what chord leads where help us build chord progressions that sound good. For example, the chord I is usually the first chord in a chord progression, and it often leads to chord V, which may lead to VI, which may lead to IV, which leads again to I and everything starts again.
Figure 6.2 shows a I-V-vi-IV progression.
This is a chord progression – not necessary in I, II, III… order, but in an order that sounds good. The chords change in a regular fashion (called a harmonic rhythm), and upon these chords we build melodies, thus creating music.
Figure 6.2 shows a very nice and simple chord progression.
As I said, we have three main chords – I, IV and V. We may add chords II, III, VI and VII between them, or we may substitute these three main chords with four additional chords, because these three also represent groups:
- I, III and VI – think of as a tonic group.
- II, IV – subdominant group.
- V, VII – dominant group.
Each of these chords has a function. Tonic is a stable chord, the beginning and a satisfactory end. It may start and end the piece. All other chords surround the tonic, and the tonic is the harmonic center of the musical piece.
A mediant and a submediant are similar to tonic, because they share a single note with a tonic chord. They may act as a substitution for tonic.
Chords VI and II lead away from the tonic, musically they lead to a different place. They are used if we want to leave the tonic behind for a moment. But they also lead to the V chord, the dominant.
Chord IV is a good, stable chord that often leads back to the tonic.
We also have chords V and VII – they are unstable, tensed and they must be resolved somehow – usually by returning to the tonic chord.
The following guidelines apply to major scales. Please note that these are guidelines, not unbreakable rules.
This chord can be placed anywhere and it may lead to any other chords.
We may use the II as a substitute for VI. It leads to a tonic, a dominant or a leading tone chord.
It may be used as a substitute to a tonic. It leads to a tonic, a subdominant or a submediant.
It leads to a tonic, a supertonic, a dominant or a leading tone chord.
It leads to a tonic or a submediant.
We may use this chord as a substitute for a tonic. It leads to a tonic, a supertonic, a mediant, a subdominant or a dominant chords.
We may use it as a substitute for a dominant chords. It leads to a tonic.
You may have noticed that any succeeding chord may be placed in the same octave as the preceding chord, or any other octave. Every chord can be inverted, as well. Figure 6.8 offers you the very same chord progression, I-V-vi-IV,, but with different inversions.
In minor scales, the rules are rather similar:
- I – we can pace this chord anywhere.
- II – it can be a substitute for VI, and it leads to a tonic, a dominant, or a leading tone chords.
- III – it can be a substitute for a tonic chord. It leads to a tonic, a subdominant, or a submediant, but also to a leading tone chord.
- VI – it leads to a tonic, a dominant or a leading tone chords.
- V – it leads to a tonic or a submediant.
- VI – it may be used as a substitute for a tonic chord. It leads to a tonic, a mediant, a subdominant or a dominant chord, and to a leading tone chord.
- VII – it may be used as a substitute of a dominant chord. It leads to a tonic chord.
In other words, when you create your chord progression, you need to define what chords you’re going to use and put them in an order you want while keeping the above guidelines in mind. Thanks to this, your chord progressions will sound nice.
The ability to use some chords as a substitutes for other chords adds more interest and variety to chord progressions.
In practice, when you create MIDI music, you don’t put any roman numerals anywhere, but you still need to know what chord you’re using, and what its function is.
But does it mean that every chord progressions needs a tonic and a dominant, since these two are considered the most important of all seven chords? Not really.
You need to remember that music theory is merely a set of guidelines that you may follow, but you don’t have to. If you want to create more experimental music, you’re free to do so. Music is a creative process and some guidelines can be ignored.
And what about seventh chords? C7, that is a C major chord with a seventh is still a tonic chord in C Major scale. When you add additional notes to your chords, these notes do not change the function of the chord, because even a C7 is still build upon the first degree of the scale, just like the G7 is build upon the fifth degree of the scale – C7 is still a tonic, and G7 is still a dominant.
You’ve learned about chord functions, and you have the theoretical knowledge to build chord progressions. As you already know, chord progressions are sets of chords, succeeding each other, placed in a logical or creative order that makes musical sense. These sets repeat throughout the entire song, or through entire verse and change to a different set of chords for a chorus.
Figure 6.9 shows a simple chord progression.
In this case the last chord, which is a fifth chord here, C Major, is a tonic, the I chord. The entire progression is made of four chords, and this last tonic chord is here simply to show you that this is where we start the progression over again.
Chord progressions can be short, made of two chords, or long, made of multiple chords. Four chords for a progression is quite a common number, though. Chord progressions can be very simple, made of only triads, or very complex, made of seventh or ninth chords, or even using non-diatonic chords and so on. This is the realm of harmony and an entire book can be written about this.
To create a chord progression, you need to know the guidelines for chord functions from the previous section. These guidelines were created based on the “fit” between the chords – some chord progressions sound good, others sound bad.
Also, chords in a progression can change once a bar, twice a bar, or in a non-standard way – the pattern of chord changes is called a harmonic rhythm.
Figure 6.10 shows the same progression but with different harmonic rhythm.
Figure 6.10 shows a very simple progression on the left, with two chords per each bar. The second progression uses chords that last an entire bar. The third progression is a bit more dynamic. In it, we have chords that last a quarter of a bar, half the bar and an entire bar.
The number of chords is limited, so a lot of musical pieces are made with the same progressions. This is normal and beginners can use these common progressions freely.
Here are some examples of common chord progressions:
- I – IV – V – I
- VI – IV – I – V
- I – IV – VI – V
- Vi – V – IV – V
- Ii – VI – I – V
You can use these progressions in your own music, or create your own progressions.
Chords for Relative Keys
Perhaps you remember when we talked about relative scales – if they have the same notes, we emphasize the key of the scale to clearly define our scale. I mentioned that chords can be used for the same purpose, to place an emphasis on the key and type of the scale.
What about the chords? These, too, can be substituted or replaced. In relative scales we always have the same chords. This means an A Minor is always an A Minor chord, both in C Major scale and in A Minor scale. But in C major it’s a sixth chord, and in A Minor, it’s a first chord. So the function changes. Here’s an example.
We have the tonic of the A Minor, and it’s an A Minor chord, made of A, C and E.
C Major is a relative major scale for A Minor scale. In C Major there’s an A Minor chord as well. In C Major, though, A Minor chord is a submediant. It works the other way around, too. In C Major, we have a C Major chord which is a tonic. The same chord is present in A Minor scale, but there it is built on the third degree, so the chord is a mediant.
How can we use this? Basically, when composing you can intertwine major and minor scales together if they are relative to each other. For example, you can build the first chord progression on a major scale, and then, using the same notes, build the same progression in a minor scale. The notes are the same, the progression is the same (for example, I-V-VI-I), but the chords are different.
Listen to an example melody with this I-V-VI-I progression. The first half in one scale, the second half is in another scale.
This is still the same melody and the same pattern of chord progression. And we have the same notes, but the chord progression in the first half (first four bars) is based on C Major scale, while the second half is based on A Minor scale. This way we can use the very same notes, but different chords to emphasize which scale are we working with.
A cadence is a part of a track that sounds like an end to a song. It may actually be the definite end of the song, but it may also be a deceptive cadence in the middle of the song that merely creates tension to be resolved with music continuing. Cadences can be found at the very end of the track, in the middle, between verses and chorus, or right before pauses and so on.
We have many types of cadences. For example, there’s a perfect cadence, in which we end the song with a dominant chord followed by a tonic chord, like on figure 6.12. These two chords may be a part of the original chord progression that repeats throughout the entire song, or they can be added just at the very end of the song, for example by substituting two last chords of the original chord progression. This works with other cadences, too.
A perfect cadence is a very satisfying ending to the song, musically and emotionally speaking (actually, a perfect cadence would occur only with proper vocing, when a leading tone of the dominant chord would be followed by a root note of the tonic chord, but don’t worry about this now).
It’s a good idea to always start a song with a tonic chord (to define the key and scale), and end the song on a tonic – or at least start and end the song with the same note.
We have the following types of cadences.
- Half Cadence
An authentic cadence occurs when we progress to a dominant chord that is followed by a tonic chord. Authentic cadence may have various types. For example a perfect or imperfect cadence, but beginners don’t have to know this so we’ll leave this for a book about harmony. Just know that perfect cadence requires chords in root position, and imperfect cadence requires chord inversions, and it’s all about the voicing.
Plagal cadence occurs when we progress to a subdominant chord followed by a tonic. This kind of cadence is often used in the middle of the song. Look at figure 6.13.
A deceptive cadence progresses to a dominant chord and it is followed by a different chord, just not a tonic one. This kind of cadence doesn’t “feel” like ending. The chord that follows a dominant in this kind of cadence is usually the VI chord. Look at figure 6.14.
A half cadence occurs with progression to a dominant chord, followed by nothing.
How to use cadences? It’s simple – find a place when you want to end the song, or prepare the listener to a pause or some other kind of change in the middle of the track – there, put the cadence chords, and you’re done. As I said, you can replace the last chords of the original chord progression with the cadence chords.
Harmonizing a Song
Harmonizing a song is all about adding chords to a melody – we can add entire chords, or parts of a chord (like dyads, that only suggest/imply a chord). By entire chords I mean adding triads, for example. And by parts of a chord, I mean note or notes of the chord that suggest the chord – for example, adding only the root and the fifth, but omitting the third.
How to add a chord to a song? A couple of techniques exist. Usually you create a melody in a given key and given scale – this already tells you what kind of chords you’re dealing with, because these chords are build upon seven degrees of a scale in a given key. When you have a melody composed by someone else and you don’t know the key, take a look at the very first note of the melody – sometimes it’s the first note of the scale used (but not always, so be careful). Or take a look at which note is the lowest, or which note is most often used in the melody – these are not the rules, but sometimes you can figure out the scale and key this way.
When you know the and the scale, you know the chords available to you. Next, take a look at the notes in a given bar that you wish to harmonize. What kind of notes are there in this bar? Usually, we harmonize the melody with a chord containing at least one note of the melody line. Sometimes, you see that note A is dominant in a melody in a particular bar – you have a couple of chords to use in such case, as a couple of them contain note A. Sometimes, the melody contain both notes A and E, and a couple additional notes, but you know that chord A Minor contains both A and E, so it can be used to harmonize the melody.
Figure 6.14 shows a simple melody, in which the first bar contains only a single note – A. This is A Minor scale, and we can start our chord progression with a tonic chord, and we know it contains note A. So we add this chord under the melody. The second bar contains note G and A. A couple of chords in A Minor scale contains note A, and a couple of chords in this scale contains note G. A dominant chord is an example, so we place it in the second bar. In the third bar we have a note B in the melody. The VII chord of A Minor scale contains note B. It also contains note G, which it shares with the dominant chord, and it strongly leads to a tonic chord, which we add in the last bar, because the melody ends with the same note that it started with. And we often end the chord progression with the same chord that we started with. Take a look at figure 6.16.
This is a very simple example of harmonizing a melody. You use the chords that contain note or notes of the melody, and you keep the rules of chord progressions and chord functions in mind, while at the same time making sure that everything just sounds good.
Figure 6.17 shows a different example, a little bit more dynamic.
Figure 6.17 shows a faster melody in C Major scale. Let’s take a look what notes we have here. In the first bar we have notes C, B and A. It’s customary to start with a tonic chord, and it contains a C note, so everything is fine.
The second bar contains notes G, A, B, C and D. It would be nice to use a chord containing a G note, because C Major chord also contains a G note (its fifth), so we would have a sense of continuum. We can use a III chord, a mediant, because its third is the G note, especially because it shares two notes with a tonic chord (E and G), and it also contains note B. G and B are the two notes of the melody in this bar.
The third bar contains notes F, E, D, C and B. The II chord, the supertonic, contains notes D and F so it should fit here nicely. The supertonic can be a substitute for submediant, the VI chord. It will be followed by another tonic chord, finishing our chord progression.
And that’s it – take a look at the notes of the melody, and add chords accordingly, remembering the basic rules of chord functions and chord progressions. And remember, if something sounds good, leave it.
You’ve learned the basics of chord progressions and harmonization. This actually completes this guidebook. You know the basics of music theory. But before we end this book, I want you to show a very simple music piece so you can see everything we’ve learned “in practice”.