Chord sequences

Chord sequences are sets of triads or seventh chords that replace one another. One short chord sequence can close and repeat throughout the song. A piece can also consist of several combinations: one for the verse, one for the pre-chorus, and one for the chorus. A song can also be one complex chord sequence that creates a constant progression. The number of triads can vary. Many funk compositions are built on a single seventh chord, but this is specific to the style. Other pieces of music tend to use multiple chords.

How do you make up a chord progression?
Experienced producers build chains with chromatisms, deviations, modulations, and other harmonic clutter. Such moves give the song interesting texture, dynamism, and drama. But it is not necessary to chase after complexity. First, ornate chord sequences may seem old-fashioned to a modern listener. Secondly, a novice composer can get confused in the branches and compose something absurd. So for starters, stick to a few rules.

Work in the same tonality. For example, A-minor includes the chords Am, Bdim (you may not use it), C, Dm, Em (usually E is played instead), F, and G. Take any of these and you won’t miss. But in a different key, you’ll have a different chord progression.

Aim for the tonic. Try to start or end with a first-step chord (tonic triad). In A minor tonality it is Am (A minor). This way, the chord sequence will sound complete and thorough. You will feel the pull yourself when you start playing.

Build on the basic chords. Take the first, fourth, and fifth steps as your foundation. These are the tonic, subdominant, and dominant. In A minor they are represented as Am, Dm, and Em (E). This is the most common chord sequence. It provides the most logical harmonic development.

Add the other steps and listen. When you have mastered the passage from the tonic through the subdominant and dominant to the tonic, try replacing one of these steps with a third, sixth or seventh. Or supplement the composition without changing the base. And be sure to listen to see if it sounds nice. If you like it, keep it.

How do you label harmonic chains?
Imagine you’ve harmonized a song, but you haven’t yet found the optimal tessitura, the pitch that would be comfortable for the vocalist, guitarist, and bassist alike. Let’s take some simple chord sequence: for example, Am – F – Dm – E. If we move it up by two tones, we get Cm – Ab – Fm – G. Another tone up: Dm – Bb – Gm – A. The notations are constantly changing.
But we understand that the general sound, the relationship of the chords remain the same, only the tonality changes. That is why many musicians began to designate chord sequences in Roman numerals, in steps. So our harmony will look like “i – VI – iv – V”. Minor chords are written in lower case, while major chords are written in uppercase.
Now the chords of any tonality are reduced to seven Roman numerals. Some musicians even use the more familiar Arabic numerals. This is, for example, the name of the chord progressions in jazz. The basic steps are I (tonic), IV (subdominant) and V (dominant). But the other steps are also very often used in music.

What are diatonic and chromatic?
A diatonic is a chord in which all the notes are arranged in pure quintals (up) or pure quartals (down). Simply put, it is a regular seven-step minor or major scale. From each of the steps, we can lay down one triad. It will either be a major or a minor scale. If, for example, in A minor tonality we want to build a minor triad from the note A, we will not be able to do this because in A minor diatonic tonality there is no C-sharp note, which is part of the A major chord.
Thus, diatonic gives us a clear set of notes, intervals, and chords. By working within the diatonic series, we avoid dissonances and chord sequences that are strange to the ear. Roughly speaking, any tonality (e.g., E major, B flat minor, etc.) is diatonic. As for chords, in major we have three major chords (tonic, subdominant and dominant), three minor chords, and one diminished chord (7th step). In minor, we have three minor chords (tonic, subdominant and dominant), three major chords, and one diminished chord (II step). As we can see, the composition remains the same, only the order changes. So the major, minor, and other “natural” harmonies (Phrygian, Locrian, etc.) are diatonic.
A chromatic scale is 12 notes arranged in semitones. Two neighboring notes form an interval called a “small second” (e.g., C and C-sharp). Within the chromatic scale, all kinds of melodies, intervals, and chord sequences are possible. But works built on the chromatic scale can have a specific sound, since in essence the composer is not limited in any way here. Any dissonant intervals and the strangest harmonic combinations will not break the chromatics.
But the careful weaving of chromaticisms into the music adds beauty and originality to it. For example, the extended C triad (Caug) or the C minor seventh chord (C7) for the A minor key are chromatisms, because Caug has a G-sharp note and C7 has a B-flat note. These notes are not part of the A minor tonality. But you can weave Caug or C7 into a song in A-minor in a way that makes them appropriate.

Simple chord sequences
Next, we’ll look at specific chains that you can put into practice. We won’t take chromatisms, as this is a complicated and specific topic. Let’s turn to combinations of triads built on seven pitches of diatonic. As we have already said, the number of chords in the chain can vary. The simplest form is a chord progression of two triads.
This form gives the song a specific coloring. There is a clear return motion. It is as if we are walking back and forth, but we cannot jump off this trajectory. And its length can be different. You can give an entire measure or even half of a verse to one chord. Or you can, on the contrary, reduce the distance and do a change for every quarter. It doesn’t matter if you’re building a chord progression in major or minor, we have several patterns anyway.

I – V (e.g. Am – E or C – G)
I – IV (Am – Dm or C – F)
I – VII (II) (Am – G or C – Dm)
I – III (Am – C or C – E)
I – VI (Am – F or C – Am)
As you will notice, there is a tonic triad in all the pairs. Any piece has a first step, otherwise the music loses its foundation or the first step becomes some other note. But there is a gravitational pull to the tonic in any case. It is required by our auditory perception.
But here is an example where we can remove the tonic from a chord sequence. Play the entire verse movement IV – V – IV – V – IV – V – IV – V (or any other, but without I). And start the chorus with the tonic. That way you will have a harmonic iteration: the verse is tossed between unstable steps, but the chorus has found a tonic exit.
The contrast between the sparse chords in the verse (take the same wandering between two steps) and the chord-saturated chorus or pre-chorus will also work great. Play, for example, the whole verse i – VI – i – VI – i – VI – i – VI (Am – F), and in the chorus – i – VI – III – V (Am – F – C – E). Experiment. Even simple moves give you an opportunity to come up with something unusual.

Patterns of three chords
Let’s complicate the harmony by adding one more link. The standard movement consists of three points: tonic – subdominant – dominant. In terms of stability, this is probably the best chord sequence in all the variety of world music. But it doesn’t fit the rhythm on 4 counts, that’s why one of the three steps is duplicated or prolonged in it. There are several modifications.

I – IV – V – V
I – IV – IV – V
I – I – IV – V
I – IV – I – V
I – V – IV – V
Why not take any of the side steps? That’s what composers often do. And the other steps can perform the same functions as the main ones: II – subdominant, III – tonic or dominant, VI – tonic or subdominant, VII – dominant. That is, they create the same gravitational force into the tonic as the subdominant and dominant, and have a similar character to them. You can either replace the basic triads with these chords or add them to the basic chord progression. You get even more variations.

I – II – V – V
I – II – II – V
I – I – II – V
I – II – I – V
I – V – II – V
I – II – IV – V
I – IV – II – V
I – III – IV – V
I – III – VI – IV
I – IV – VI – V
and so on
Twelve-chord chord progression.
It is essentially the same basic three-chord sequence I – IV – V, but stretched out over 12 bars. You play the first 4 bars in the key, then 2 bars in the subdominant, go back to the key and stand on it for 2 bars, then 2 bars on the dominant and 2 bars on the tonic. You can vary the beginning and the end by playing the dominant in the very last measure as a transition to the next pattern, and add the subdominant before that. In general, you will get the following scheme: T – T (S) – T – T – S – S – T – T – T – D – D (S) – T – T (D).
This is a quite recognizable chord sequence for guitar, it is used in many blues pieces. But it is even more commonly used as an accompaniment for improvisation. One guitarist plays the combination with chords and the other plays a jam solo to it. At some point they switch. The accompanying musician also sets the characteristic rhythm for this form, the shuffle. It’s a trio pulsation (one-two-three-two-two-three) without the second beat. If you understand the durations, it is the repetition of the quarter-eighth pattern.
The chord sequence for blues is also played on a single guitar. To do this, you need to set the harmony from time to time with chords and maintain the blues rhythm. Intervals and power chords can also be played. It’s not uncommon to use seventh chords and sextachords instead of triads. The rest of the time you have to do solo insertions. And if you play this chord sequence on the piano, it’s easy to break it down into a bass-harmony part (for the left hand) and a solo part (for the right hand).

1950s Progression.
This combination was especially popular in the ’50s, as its name makes clear. It is based on the same movement I – IV – V in major. Add a sixth step and you have a 1950s scheme. The subdominant was in some cases replaced by the second step. Thus, we get two varieties of this chain.

I – VI – IV – V (for example, C – Am – F – G)
I – VI – II – V (C – Am – Dm – G).
This beautiful chord sequence was invented even earlier. It was even used in early classical music. But in the 1930s, several hit songs were based on it, and it became associated with the vocal music of those times. And in the ’50s, it reached its highest popularity and even became a basic element of an entire genre – doo-wop.
Sometimes this chord sequence is called “doo-wop progression. In doo-wop, vocalists perform both the main melodic part with lyrics and the harmonic part of the accompaniment. They often sing just the “doo-wop” syllables by which the genre is named. Four vocalists can essentially make up a full band. But the performances still involved drums, saxophone, piano, guitar, and double bass. And it all necessarily moved along the path I – VI – IV (II) – V.

Harmonization of a scale
So, each natural (diatonic) scale has 7 steps. The chromatic scale has 12. Theoretically from each note we can build 4 triads. The tricons are based on the tertiary scale, which may be large (4 semitones) and small (3 semitones). Accordingly, we can build a major chord (4+3), a minor chord (3+4), a diminished chord (3+3), and an extended chord (4+4).

But within the natural (diatonic) scale, you will not be able to build 4 triplets on each step. For example, in C major tonality, we can only build a major chord from the C note. If we try to play a C-minor triad, we will get the E-flat note, which is simply absent in C-major.

This gives us a limited set of chords within the tonality. In the major tonalities, you build a major chord from step I, minor chords from II and III, major chords from IV and V, minor chord from VI, and a diminished chord from VII. And there is no other way. Otherwise, we will have notes that are not part of the scale. These, of course, can also be used, but with great caution.

Using seven chords within a single key is called harmonizing the scale. Use any of the triads in this set, and you’ll have a beautiful chord sequence. Some songs are even built on sequencing these chords up (I – II – III – IV – V – VI – VII) or down (VII – VI – V – IV – III – II – I). Such combinations, too, can be applied, in whole or in part.

Minor and modal chains
The chord sequences discussed above also apply to the minor, including ascending and descending movements. A minor has the same chord progression as a major, only the order changes. I is a minor triad, II is a diminished triad, III is a major triad, IV and V are minor, and VI and VII are major.

How do you use chord sequences when writing music?
There is no single correct algorithm for composing music. You can build a composition around a text, around a rhythmic framework, around a hook or a musical idea. But the traditional method is to harmonize the vocal melody. You simply match the chords to the melody and listen to which combination you like best. You have to make sure that there are no dissonances or tessitura conflicts between the melody and harmonic lines.

The opposite way is to build a melody based on a chord sequence. Harmony already gives you a lot of sounds that can suggest melodic direction. And if you’re out of ideas, try recording a combination of triads first, and then do some improvisation, humming whatever comes to mind over the recording. Or just compose phrases from the notes that go into the harmonic texture.

How do you put together a chord sequence? We learned the first way at the very beginning of this article: take any chords that are part of a tonality. Swap them around as you like. Listen and leave the combinations you like the most. In order not to get confused, lean on the tonic, you will always be drawn to it.
The second way: go through the chains suggested in the article. Take the combinations from the tables. Try two-chord combinations.

Try three-chord combinations. Maybe you’ll like the 12-chord blues. Maybe a 50’s chord sequence will suit you. Work with the gold sequencing. Experiment with an ascending or descending movement.
Once you’ve mastered the steps and functions, try breaking the system down. Where there should be a minor triad, play a major triad. Listen to what you get. Try adding some totally inappropriate chord to the standard scheme. Look for beautiful transitions in parallel tonality. Don’t short-circuit one pattern, but combine different variations.

A very useful activity is to take apart popular songs, both contemporary and established classics. Look at chord sequences in R&B, rock, reggae, and other styles. See how famous musicians build harmony. Pick chords and break them down into steps. You’re sure to find many examples that will surprise you. Grasp the logic and apply it to your songwriting. Learn from the best.
In conclusion, it’s worth saying that you shouldn’t get hung up on chords. There are plenty of elements that will make your piece of music original and expressive. These include tenacious hooks, a beautiful melody, a killer rhythm, an unusual compositional structure, instrumental timbres, and more. But if you add to all this a unique harmony, you stand a good chance of creating something outstanding.
No inspiration – run some software chord sequence generator. But don’t let circumstances get in the way of your creativity.