Guidelines for writing a chord progression

Question

I am trying to understand how does notes relate to each other when writing a chord progression.

I understand that when composing on a Major scale chords acquire a function depending on the degree of the scale, these functions are as follows:

Functional Harmony Chord Functions

I ,iii, vi -> Tonic
V , viiº -> Dominant
IV, ii -> Sub Dominant

* Uppercase = Major, Lowercase = Minor, º = diminished

Example on C:

C ,Em, Am -> Tonic
G , Bº -> Dominant
F, Dm -> Sub Dominant

Tonic Function Chords are those which contains the third degree of the scale which should define the overall sound of the scale.

Dominant Function Chord are those which contains the seventh degree on the scale, the seventh degree of the scale wants to go first degree of the scale, thus Dominant Function chords want to go to a Tonic Function Chord.

Sub Dominant Function Chords contain the fourth degree of the scale, which has no leading tone (seventh degree).

So as far as I know the progression tendency is as follows:

Dominant <-> Sub Dominant <-> Tonic

All that means is that chords are collections of scale degrees.

Each scale degree has its own tendencies. The collective tendencies of a chord’s scale degrees in combination is the chord’s function.

But how are this tendencies defined? I don't really understand why certain notes want to go move to certain notes of the scale, also how can I apply this on another scale, for example a minor scale or a major pentatonic scale.

Where can I learn about how notes tend to move in a chord progression?

Lastly, I want to assume that this is the way that chord progression charts work? - *Chord Progression Chart Example

How can I create a chord progression map for a scale?

Answer 1

It sounds like you're trying to find some general musical rules, and make music according to those rules. That's an interesting exercise, but it's not generally how people write music, partly because such rules can be quite specific to the style of music you want to write.

As an example - you've mentioned I, IV, V, and the V->I motion. But there are some styles of music that tend to avoid V, and the V-I motion.

But how are this tendencies defined? I don't really understand why certain notes want to go move to certain notes of the scale, also how can I apply this on another scale, for example a minor scale or a major pentatonic scale.

One way of justifying the idea that notes 'want to' go in some direction is the leading tone. This justifies the I->IV and V->I motions.

Another justification is that roots of chords want to move to roots that are harmonically-related - that have simple frequency ratios between them. This can be used to justify jumps of a fourth or fifth.

The tonic is seen as "stable", and therefore motion to the tonic can always be seen as a move 'home' to stability.

Of course to state the obvious - notes don't actually 'want' to go anywhere - it's the listener that might want them to go somewhere. But different listeners might want different things!

Where can I learn about how notes tend to move in a chord progression?

I would recommend taking some theory materials (like Steve Mugglin's chord chart that you found), and comparing what they say to the actual behaviour of some pieces of music that you like. You will find that some theory rules are more important for some styles of music; other rules are more important for other styles. Sometimes you'll have to observe the rules yourself - not all styles of music are particularly well-documented!

Answer 2

Honestly you will find many explanations and I would say that you should not overthink it, otherwise it will block you more than anything else. I would like to give you just 2 simple pointers, but remember nothing is entirely scientific. Like a lot of people, I often go back to "if it sounds good to me, then it's good". Some people find sus2 chords dissonant where I actually find them pleasing. It is all subjective.

The first thing I would say is that a lot of chord progressions revolve around the leading tone idea. That would lead you to think about something very technical like establishing the key and all, but if you look at it simply, there is just something pleasing about chromatic movements (i.e. when you play 2 chords in a row with a note that is only a half step away). In the major key you have this between 3 and 4, but more importantly between 7 and 1.

You'll find that most chord progressions are pleasing when they have one of this movement. Especially if the voice leading emphasises it. I would say this is one of the reasons why I IV V sounds good because any combination of transition has a chromatic movement.

The reason why I say you can forget a little bit about further theory is because this simple idea is what I think sometimes make out-of-key chords sound good.

Take "Something" by the Beatles, it starts with C, Cmaj7, C7, F. This progression has a very nice chromatic movement from one chord to another with the highest notes (C,B,A#,A).

If you take this concept further, a lot of progressions by Radiohead get away with weird progressions thanks to the same idea. But when you go too far, it makes it very hard for the singer to find a melody on top of it because classic scales are so strongly engraved into our brains.

The other thing I wanted to mention is also related to voice leading. When you move from one chord to another, the transition for each note is either the same movement for all the notes (what happens when you move the same chord shape up or down), it can move in the same direction but with slightly different intervals, or it can move in opposite direction.

The accepted view on this is that same movement is boring, slightly different is better and opposite is best. This is why sometimes the same chord progression may sound too "predictable" (for lack of better word). This is also why jazz musicians usually push it to the extreme and try to use chord inversions to move as least as possible. It sounds arguably "sophisticated" (for lack of better word).

Now if you look at the progression between V7 and I in the major key, there is a beautiful movement that is actually 2 chromatic movements (like in my first pointer) but they move in opposite direction. In the key of C major, you've got the B "resolving" to C, while F is going to E in the opposite direction. This is arguably why V7 to I sounds even better than V to I and considered the perfect cadence.

As you can see, these pointers explain a little bit the relation between the notes of the chord, but also it helps finding good ways to add a bit of quirkiness. It helps you find out-of-the-key chords that will sound like they fit. They are probably other ways to explain this, but I find voice leading to be an underestimated subject.

Answer 3

I think you need to change a few things in your summary of functions.

I ,iii, vi -> Tonic

Only I has the tonic function. I've seen some people say your substitute iii or vi for I, apparently because they all share the third scale degree, the mediant, or ^3. But while that is a harmonization options it shouldn't be confused with tonic function.

Tonic Function Chords are those which contains the third degree of the scale which should define the overall sound of the scale.

Tonic function is the tonic chord, the major or minor triad built on the tonic degree.

The subdominant (pre-dominant) and dominant functions are fulfilled by several chords as you listed - like V or viio for dominant - but the tonic is different.

Perhaps one way to think about it is the tonic is the ultimate point of stability and resolution and as such there isn't any ambiguity about the identity of the tonic chord.

Dominant <-> Sub Dominant <-> Tonic

Functional flow is one direction: subdominant (pre-dominant) to dominant to tonic.

Anything else is a retrogression from the perspective of functional harmony.

Sometimes you will find a progression like V IV6 V but those can be described as prolongations where the essential harmony is simply V.

Also, not fulfilling the functional flow has it's own expressive potential. The obvious case is the deceptive cadence. The whole deception is not fulfilling the functional move to the tonic. Stylistically it's incomplete and sets up and expectation for another phrase.

Guidelines for writing a chord progression ...[how do] chord progression charts work?

In my opinion progression flow charts don't work for writing harmony, because they don't directly address phrasing, cadences, and form.

You question is tagged with "functional harmony" so I assume the context is common practice, classical style, not pop progressions like ||: I V vi IV :|| which aren't properly functional.

A better way to write chord progressions to think of categories of progression within common formal structure. There are different way to categories, but here are three general concepts:

• prolongation harmony
• sequential harmony
• cadences

A simple formal framework is being, middle, end. Prolongations can support beginning, sequential harmony is a common way to link sections in the middle, and cadences end phrases and sections.

A simple design could be:

||tonic prolongation | half cadence || sequence        |       full cadence ||
||: I IV6/4 I        | ii6 I6/4 V  :||: V6/ii ii V6 I  | I6 IV I6/4 V7 | I :||

The idea is that it's less important which specific chords you use - ii6 versus IV that using the appropriate category of harmony within the structure of the phrases. You wouldn't want to start out a piece using harmonic material appropriate for an ending. Syntactically it doesn't make much sense.

Of course this isn't the only way to approach writing chord progressions, but it's an alternative to the flow charts. Think about how harmony works within the structure of phrases.