In this lesson I gave you a step by step process you can use to start writing songs with the guitar.
In today’s lesson we’ll delve deeper on an important topic for songwriters: Diatonic chord progressions.
A chord progression is a series of two or more chords played in an order.
Diatonic chords are chords that are made of the notes of a particular scale/key.
Songwriters also use non-diatonic or chromatic chords, but understanding diatonic harmony is the place to start when looking for chord progressions to use in your songs.
Though diatonic harmonization can also be applied to the modes, it is most commonly applied to major and minor keys.
In this lesson we’ll focus on the major key.
Though minor keys go through the same harmonization process, they get a bit more complex since there are variations of the (natural) minor scale – the harmonic and the melodic minor. Thus they deserve a lesson of their own.
Diatonic scale harmonization
To harmonize a scale we simply stack intervals of a third over each note to derive the underlying chord.
We’ll go through this process using the scale of C major. (To explain a music theory concept or process the key of C major and its relative minor A are the most convenient since they have no sharps and flats).
The following are the notes of the C major scale: C, D, E, F, G, A, B, (C)
And this is how C major scale could be played in one octave, on one string.
The first step to harmonizing a scale is by stacking an interval of a third over each note. (An interval means the distance between two notes).
To easily find this note, go to the scale degree you want to harmonize, and skip a note. For instance in the key of C major, C is harmonized with E, D with F, E with G etc.
This is the scale of C major harmonized in thirds:
So far we have only harmonized the scale in double stops, in intervals of a third.
By stacking another layer of thirds we get the chords that harmonize the scale.
We do this by repeating the process and stack another interval of a third over each double stop: C – E – G, D – F – A, E – G – B, F – A – C etc.
The result is a set of chords (also called triads since they’re made of 3 distinct notes) you can use every time you want to write a song in C major.
In this lesson on triads we go deeper into how each triad is formed and how they can be used.
These are the triads in the key of C major:
C major (C, E, G)
D minor (D, F, A)
E minor (E, G, B)
F major (F, A, C)
G major (G, B, D)
A minor (A, C, E)
B diminished (B, D, F)
These chords create the formula for all harmonized major keys: Major, minor, minor, major, major, minor, diminished.
Memorize this formula if you’re a songwriter since through it you can find the chords for any major key.
For instance the triads of the G major key are:
While the triads for the E major key are:
So on and so forth with all the 12 major keys in music.
Diatonic chord progressions
Now that we know which chords are in each key, we need to learn which chords sound good together.
While trial and error won’t hurt, and you can’t go very wrong since you’re using chords in the same key, there are certain chords that progress better to one another.
In the next section I’ll give you an overview of the theory behind diatonic chord progressions.
It is important to keep in mind that the following “music theory rules” are not rules at all. They’re simply best practices great musicians have tried and tested before us.
When learning a piece of music you may find things that seem to contradict these rules.
You may stumble upon chords that do not fit in any key (non-diatonic) and still sound great.
Likewise, when creating music you may stumble upon a chord progression that sounds good but is not “theoretically explained”.
If you do, trust your ear. Never remove a chord from a progression simply because your present knowledge of music theory cannot explain it!
Functional harmony is a way of thinking about the purpose of chords in relation to each other as well as to the main chord progression.
Each of the 7 chords that can be derived from the C major scale serves a particular purpose.
Note: We can derive more chords than seven from one major scale if we add 7ths, 9ths, and other extensions. We’re only limiting ourselves to triads to keep things simple. We’ll also touch the dominant 7th (the 5th degree of the scale, G in our case, harmonized with a 7th) because it’s frequently used in many genres of music.
Before explaining the purpose of each chord in the scale, we’re going to assign a Roman numeral to each chord.
Major chords are assigned an upper case numeral and minor chords a lower case numeral.
I – C major
ii – D minor
iii – E minor
IV – F major
V – G major
vi – A minor
vii (dim) – B diminished
Next, we’re going to group these chords into three chord families, depending on their function.
Tonic function: I, iii, vi
The tonic is where the music starts and where the music finishes. It serves as the home-base of the music.
The tonic chord (I) is the most important chord in the progression. It’s always used to finish songs and keeps getting referred to many times during the song.
Chords iii (E minor) and vi (A minor) have two common notes with the tonic chord and can have a tonic function too.
Tonic chords are the most stable and have no dissonant intervals within them.
Dominant function: V, vii dim
Chords of the dominant family are unstable and want closure by resolving into tonic chords.
In the key of C these would be the chords G major and B diminished.
The chord progression V – I (also called a perfect cadence if used as an ending) is the most commonly used diatonic chord progression, and used to finish almost any song written in the major key.
The V chord is usually turned into a 7th chord, which gives us a V7– I (G7– C) progression when used as a cadence.
V – I, V7 – I
The vii dim – I (B dim – C) chord progression is rarely used and is usually replaced with the Min 7 (b5) chord.
Subdominant function: ii, IV
The purpose of these chords is to prepare the dominant.
The V – I chord progression is rarely used on its own, and is usually preceded by either the ii (D minor) or the IV (F) chord.
ii – V – I, ii – V7 – I
IV – V – I, IV – V7 – I
Common diatonic chord progressions
We have already explored some diatonic chord progressions in the previous section.
The following are some other common diatonic progressions:
I – IV – V (I), I – IV – V – IV
Ex 1 is the popular I – IV – V (C – F – G) chord progression while Ex 2 is a variation of it I – IV – V – IV ( C – F – G – F).
Note: The 12-Bar Blues is made of a variation of this chord progression. Go to this lesson if you want to learn more about blues guitar riffs.
I – vi – ii – V – (I)
This chord progression starts with two chords of the tonic function – I and vi (C and A minor), proceeds to a chord of the subdominant function – ii (D minor), to the dominant V (G) and finally resolves to the tonic chord.
vi – iii – IV – V – (I)
This chord progression starts with two chords of the tonic function – vi and iii (Am, Em), moves to the subdominant chord IV (F), to the dominant V (G) and resolves to the tonic chord.
Canon: I – V – vi – iii – IV – I – IV – V
Chord progressions are not necessarily short.
Nicknamed “the canon” because it was made popular by Pachelbel’s canon, this diatonic 8 chord progression was resurrected in the 1970’s and has been used in popular music ever since.
Conclusion: Where to go from here
There are many ways you can experiment with these formulas to create diatonic chord progressions.
However keep in mind that in songwriting, coming up with an original chord progression is not a goal worth pursuing.
Whatever diatonic chord progression you come up with has probably been used by others many times before.
What matters is what you do with that chord progression.
The melody, the rhythm, the texture, the lyrics and other musical elements are what make two songs that use the exact same chord progression sound completely different.
You may consider giving a donation, by which you will be helping a songwriter achieve his dreams. Each contribution, no matter how small, will make a difference.