Any major scale gives three major triads that together include a every note of that scale. They are based on the first, fourth, and fifth scale degrees (the tonic, subdominant and dominant).
I = Tonic
IV = Subdominant
V= Dominant
These chords will harmonize with any note of the scale.
Three-chord tunes are more common, since a melody may then dwell on any note of the scale. Often the chords may be selected to fit a pre-conceived melody, but just as often it is the progression itself that gives rise to the melody.
The three-chord I – IV – V progression, a particularly popular kind of circle progression, can be placed into a four-bar phrase in several ways that have been put to endless use in popular music.
- I – IV – V – V. (The Beatles’s “Lucy in the Sky with Diamonds”)
- I – I – IV – V. (The Rolling Stones’ “Get Off Of My Cloud”)
- I – IV – I – V. (Solomon Linda’s “Mbube”/”Wimoweh”/”The Lion Sleeps Tonight”)
- I – IV – V – IV. (Chip Taylor/The Troggs’ “Wild Thing”)
This basic harmonic pattern occurs in many other pop songs—the output of Phil Spector might also be cited. They may be varied by the addition of sevenths (or other scale degrees) to any chord or by substitution of the relative minor of the IV chord to give, for example, I – ii – V. This last is heard, for example, in The Beach Boys’ “Good Vibrations” (“Got to keep those….”). This sequence, using the chord based on the second scale degree, is also used cadentially in a common chord progression of jazz harmony, the so-called ii-V-I turnaround, on which are based the more ornate Coltrane changes.
Any of these progressions may be transposed into any key so that, for instance, the progression I – IV – V in the key of A will be played A – D – E, while in the key of C the chords will be C – F – G.
While this does not represent the entire harmonic structure of a piece, it may readily be extended for greater variety. Frequently an opening phrase of the type I – IV – V – V, which ends on an unresolved dominant, may be “answered” by a similar version that resolves back onto the home chord, giving a structure of double the length:
- I – IV -V – V
- I – IV -V – I
Additionally, such a passage may be alternated with a different progression to give a simpler form.
The Tonic chord I
Meet the tonic chord, which comes from the root note of the key you are playing in. The tonic chord is a major chord and you will find that your songs will rarely end on anything but this chord. (There are always exceptions!)
Now, go back and play those I, IV, V progressions, then when you want to finish them, play the tonic chord. It sounds resolved. Now try playing anything other than the tonic to finish the song. The song doesn’t sound resolved does it? Even if you physically finish on chords IV or V, your musical mind will be finishing on I. Try it and see.
The Dominant chord V
The dominant chord is a major chord. It is the strongest and most important chord because it leads us back to the tonic. Chords that lead back to the tonic are often described as having a dominant function and hence the name dominant.
A great way of ending a phrase or a song is using the V-I progression. This is also known as a cadence. Try it on your guitar.
Now try V7 – I. The dominant 7th chord is always a great chord to use when returning to the tonic as the 7th creates dissonance (tension) and your ear subconsciously wants to hear harmony.
The Subdominant chord IV
The subdominant chord is also a major chord. The IV chord is one of many chords that can lead to the dominant chord and hence it is pre-dominant or subdominant.
The chord progression IV-V-I is one of the strongest progressions in music. Try this on your guitar. This is a really strong way to end a phrase or a song.
The chord progression IV-I is called the plagal cadence. Listen out for this one in church music as it often ends hymns. It is informally known as the “amen” cadence. Can I get an amen?
The same major scale that gave us 3 major chords will also provide us with three relative minor chords, one related to each of the three major chords. These are based upon the second, third, and sixth scale degrees and stand in the same relationship to one another as do the three majors.
ii, iii, vi chords
Using these minor chords in your songwriting will add some depth and color to your compositions.
The supertonic chord ii
ii chord is the strongest pre-dominant chord because it resolves to V very easily. One of the most common progressions using ii is the ii-V-I progression. Jazz uses this example fairly regularly. ii can move to IV or vi, although this isn’t as strong as ii-V.
The submediant chord vi
This chord is the relative minor for the key that your are composing in. Also called the submediant, it acts as a weak predominant. vi progresses well to IV or ii but generally doesn’t follow these chords. Try the progressions I-vi-IV-V and vi-IV-V-I. Can you hear the heavens rumbling? Another good progression is I-vi-IV-ii. Are the skies getting dark?
Next try the progression vi-ii. Now remember that in the supertonic chord section, ii progressed well to V then I. So try vi-ii-V-I. Has that bolt of lightning struck yet?
Before we discussed the cadence V-I to end a passage or song. Compare the progression V-vi. Deceptive isn’t it. Funnily enough it is called the deceptive cadence and adds some nice suspense, especially if you end a song with it.
The mediant chord iii
The mediant chord not used that often in the major keys for songwriting and is found more often in the minor keys. This doesn’t mean that we should avoid it completely and I find that the iii chord can add some interesting colour, especially in a bridge. iiirarely moves to V and generally leads to the chords vi, ii and IV.
Some nice progressions using iii are iii-vi-ii-V, iii-ii-V and iii-IV-V. Experiment and see what you can come up with.
That leaves us with only one more chord, called the leading tone. We’ll learn about it in our next lesson: