Introduction to Practical Music Theory and the Circle of Fifths

Contents:

Introduction

This article will demonstrate how to use the circle of fifths to compose a simple chord progression in any major or minor key. We will also briefly discuss the topics of chromatic pitch, intervals, chords, modes, and chord progressions, and how this information applies to the circle of fifths. This information can be applied to any tonal instrument and is great as an introduction to the world of music theory. Please refer to the following diagram for an example of the circle of fifths.

The outermost circle can be used to represent the major keys. The next circle inward represents the minor keys. Finally, we have the diminished chords, closest to the center. One of the most common uses for this tool is to help find the fifth interval of a major or minor scale (we will discuss the basics of intervals later in this article). If you select the key you want and move one space clockwise, that is known as a perfect fifth. Intervals are typically described relative to the major scale, especially when talking about chords. If you move one space counterclockwise, you have moved to the fourth interval. This is why the circle of fifths is also sometimes referred to as the circle of fourths. If you’re not sure what this means, keep reading, we go more in-depth on intervals a bit later on.

There are other ways to interpret the information on the circle of fifths, but this way is best for the purposes of this article. If you like the design we’ve created of the circle of fifths, we have it available for purchase in the shop as a digital printable poster. Your support will help us continue to make useful tools for musicians in the future!

Before we make our chord progression, we need to discuss some of the fundamentals of music theory. Let’s briefly touch on what the circle of fifths actually is. Simply put, the circle of fifths is a chart made to organize the twelve chromatic pitches (or tones) and how they relate to each other. If you’re brand new to music theory, you might have some questions like: ‘What is a fifth?’ and ‘What is a chromatic pitch?’. Not to worry! We are going to explain these terms in a beginner-friendly way so you can start applying them to your music right away!

What is a chromatic pitch? In simple terms, a chromatic pitch is one of the twelve notes that can be played on a chromatic instrument such as a piano or a guitar. As mentioned in the previous paragraph, the circle of fifths is a system for arranging these notes to show their relationships. Each of these notes is separated by what is called a half-step. When you move by a half-step this just means that you have moved from one note to the note directly beside it. In turn, a whole step is when you play a note, skip one half-step, and play the next note in line. This can be done either going up in pitch or down in pitch. When you have played 12 half-steps in a row, all moving in one direction, the cycle repeats itself and you will have played one octave of the chromatic scale. For example, if you start on the C note and from there play 12 half-steps going up in pitch you will land on the next C note, one octave higher. These two notes share the same name but are different in pitch. This is because the higher note is double the frequency of the lower one, hence the two notes form a perfect octave. Pretty cool, right?

That is all we are going to discuss regarding octaves and the chromatic scale in this article because it’s a whole other topic unto itself.

Intervals and Scale Degrees

We are now going to arrange the notes of the C major scale into intervals. Why the C major scale? In short, this scale is easy to demonstrate due to the fact that it contains no sharps or flats. It can be played on the piano by using all the white keys starting with the C note (of course). The notes of the C major scale are C, D, E, F, G, A, and B. For this scale C is the root note, also called the tonic. Assigning these notes to a numeric value based on the order in which they appear in the scale will give us the intervals. These intervals can also be referred to as scale degrees. It’s important to note that each scale degree has a chord related to it. This is key to creating a chord progression with the circle of fifths. For now, we will just use regular numbers for the intervals, but later on, we will introduce a formula using roman numerals to identify our scale degrees and respective chords.

Let’s arrange the C major scale into intervals like so:

C - D - E - F - G - A - B

1 - 2 - 3 - 4 - 5 - 6 - 7

Next, we will answer the question: ‘What is a fifth?’. We first need to ensure we understand the concept of intervals and the major scale. Notice in the above diagram how G is the fifth note in the C major scale. This means that the G note is the fifth interval, or scale degree, in this scale, in other words, G is the fifth of C major. When we assign each note a number in our scale, starting with the root, in ascending order, we have its interval.

Now take another look at the circle of fifths. Each movement clockwise on the circle is a perfect fifth from the note you started on. G is the fifth interval of C major, D is the fifth interval of G major, and so on. If you move one space counter-clockwise, that would be the fourth interval. F is the fourth interval of C major, Bb is the fourth interval of F major, and so on. This pattern is the same for the minor keys. For example, E is the fifth interval of A minor, B is the fifth interval of E minor, and so on. Note that this is a basic understanding of how to use the circle of fifths. There is actually a lot more information that you can glean from this tool if you know what you’re looking for and where to look. To keep it simple, we won’t be going too in-depth on this topic, but we will be demonstrating how to use the circle of fifths to find all the intervals in a specific key a bit later on.

Chords

With your new understanding of intervals, let’s talk about chords. In simple terms, a chord is three or more notes grouped together. Typically, these notes will sound harmonious when played at the same time. There are many different types of chords with qualities that set them apart from the others. Some of the most common types of chords are major, minor, diminished, and augmented. As a beginner, it is highly recommended that you develop an understanding of these chord families. For this discussion, we will be focusing on the major and minor triads. A triad is just a term for a three-note chord. Every chord family has a formula based on the major scale's intervals.

The major chord formula is as follows:

This means that the notes which make up a major chord are the 1st, 3rd, and, 5th intervals of the major scale. Now, let’s look at the intervals of the C major scale again.

C Major Scale Degrees:

Major Triad Formula:

If we take the 1st, 3rd, and, 5th intervals, we get the notes C, E, and G. These notes make up the C major chord. That’s all the information you need to make a C major chord! If you are playing these three notes at the same time, you are playing some form of the C major triad. This formula is always the same for any major chord. Simply find the intervals in the major scale you are playing in, then pick out the 1st, 3rd, and, 5th intervals and you have your major chord.

Let’s look at another example in a different key. This time, we will use the key of A major and we will find our major chord with our 1 - 3 - 5 formula. The intervals or scale degrees of A major are as follows:

A Major Scale Degrees:

Major Triad Formula:

To make our major triad, use our formula and find the 1st, 3rd, and, 5th intervals. This gives us the notes A, C#, and E. This is the A major triad. So simple, right? Now you know how to make a major triad in any key, as long as you know the intervals of your scale.

That covers major triads, now what about minor chords? Just like the major triads, the minor triads have a formula as well.

Below is the formula for the minor triads:

As you can see, it is very similar to the major triad, with one key difference. The 3rd interval has a 𝄭 symbol next to it. This means that the 3rd interval is played a half step lower than it would be if you were playing a major chord. In other words, it's a flat 3rd. This is the only difference between a major and minor triad. It seems like a small thing, but that one-note half-step goes a long way in changing the feel of the chord. Try playing an A major chord and an A minor chord one after the other on your instrument to get a sense of how different these chords are from one another.

There is more than one way to identify a minor chord. One simple way is to find the notes of the major chord first and then flatten the 3rd interval. This is a good method to get used to because it will enable you to find major and minor triads easily. Let’s look at an example.

We will use the A major triad.

To turn it into a minor chord we flatten the 3rd interval and it becomes this:

Because the C note is a half-step lower (or flat) from C#, the notes for the A minor triad are A, C, and E. The 3rd interval of this chord is flat compared to its major counterpart, this is also referred to as a minor 3rd. We have used the A major triad to identify the notes in the A minor triad. This method will work for any minor chord as long as you already know the notes for the major chord. You can reverse this method to identify a major triad using a known minor chord. Simply make the 3rd interval of the minor chord a half-step higher (or sharp) and you have the notes of the major chord.

Another method to identify minor triads is to use the scale degrees in the A minor key and find the 1st, 3rd, and 5th intervals just like we would for a major chord. Since we are already using the notes for the minor scale, we do not need to change the 3rd interval to make it flat because, in relation to the major triad, the 3rd interval is already where it needs to be. Let’s look at an example, this time we will use the A minor scale.

A minor scale degrees:

Minor chord formula:

Since we are only using the 1st, 3rd, and 5th intervals, we don’t need to worry about the other scale degrees for now. Just note that the intervals with a 𝄭 symbol next to them are played a half-step lower in comparison to their major counterpart (or parallel major). As we mentioned earlier, we do not need to change anything using this method because the interval is already flat when compared to the major chord. When using these formulas for making chords, everything will always relate back to the major scale. This is why it's so important to learn the major scale first. Everything that you learn afterward should make more sense because this is what it all relates to.

With this information, you can now identify and build major and minor triads in any key using scale degrees and chord formulas.

Introduction to Modes

C Major Scale:

A Minor scale:

This is a good time to talk about relative minor scales. Take another look at the notes in the C major scale. Now, look at the notes in the A minor scale. These two scales share the same notes. The difference is in what order these notes are played. For C major the starting point (or tonic) is the C note. For A minor the tonic is the A note. This is the relationship between relative majors and relative minors. Every major key has a relative minor key that shares the same notes and vice-versa. They simply start on a different tonic from each other, hence changing the context and feel of the scale.

The topic of relative majors and minors can also serve as an introduction to modes. You see, the minor scale (also called the aeolian mode) is just one of the modes of the major scale. When you take notes of any major scale and change the point at which you start playing the scale (or you change the tonic) you are actually playing a relative mode of that major scale. The sound and feel of the scale end up being quite different from the relative major because the context or reference point is different from where you started in the major scale.

In the near future, we will be publishing an article focusing on the topic of modes. For now, if you’re interested in learning more about modes, try doing research elsewhere to help broaden your understanding. If you’re interested in reading our future articles on music theory, please sign up for our e-mail list for updates on new content as soon as it gets published. We really appreciate your support!

 

The Roman Numeral Chord Formula

Next, we will discuss the roman numeral system for identifying chords. Let’s use the C major scale, once again, as an example.

Next, we will replace the intervals with a formula that uses roman numerals to represent our chords. It will look like this:

If you have never seen this method before, you are probably wondering why we are using roman numerals. The numerals in capital letters represent the major chords and the lowercase ones are for the minor chords. You’ll notice that the last chord has a ° symbol next to it. This is the symbol for the diminished chords. To use this formula we take the roman numerals and replace them with their respective scale degrees for this key, we then have all the major and minor chords ready for us to begin arranging into a progression. This formula is the same for every major key. One thing to note about major progressions is that they tend to sound happy, and are often likened to fun campfire music. Of course, the feel is going to change depending on the context in which the chords are played, so this is a general take on major chord progressions. The chords we have for C major, using this formula are as follows:

Chords with the lowercase “m” beside them represent the minor chords. The last chord in the line has the abbreviation “dim” next to it because it is the diminished chord. Major chords are simply represented by a capital letter by itself.

This formula is the same for every major key, meaning if you know the scale degrees for the key you want to play in, you can use this formula to find the major and minor chords in that key. This is where the circle of fifths comes in so handy! For now, we’re just going to focus on the major and minor chords and we won’t worry about the diminished chord. We will discuss how to use diminished chords in a future article.

The following is the roman numeral formula for the minor keys:

This can be applied to any minor key. You just need the scale degrees of the key you want the cords for, replace the numerals with the corresponding scale degrees and you have identified the major and minor chords for your minor scale. It's that easy! We will soon demonstrate how to apply these formulas to the circle of fifths to quickly identify the chords in any major or minor key.

 

Chord Progressions

Now, let’s briefly discuss what a chord progression is. In simple terms, a chord progression is an arrangement of chords placed in a certain harmonic order. A chord progression can be used to emphasize the relationships between notes in a key. There are many popular chord progressions that are used and reused across many different genres and styles of music. Think of these progressions as patterns or blueprints for creating new music. These patterns are often referred to as cadences and when used correctly, they can be powerful tools for artistic and emotional expression. We won’t be going too in-depth on the details of cadences in this article as it is a very deep subject. In a future article, we will discuss this topic more fully.

With some of the basics and fundamentals of music theory looked after, we are ready to put together a chord progression using the circle of fifths.

How to use the Circle of Fifths to make a Chord Progression

If you’re new to music theory and you’ve made it this far, congratulations! You’ve learned some of the important basics of music theory and now you are ready to start using your newfound knowledge. Well done! If you already knew everything discussed previously in this article, and just skipped to this part, that’s also great! Maybe you’d like to come back if you need a refresher, or you’d like to use this article as a reference for your students. In any case, thanks for reading and we hope you enjoyed the article. Now, let’s see the circle of fifths in action!

For easy future reference, we will break down the process of making a chord progression with the circle of fifths into steps like so:

 

Step 1. Select your key

For a major key, choose any one of the notes in the outer ring of the circle. This is the root note of your key, also known as the first interval or tonic.For a minor key, choose a note from the second ring of the circle. This is the root note of your minor key. For a minor key, choose a note from the second ring of the circle. This is the root note of your minor key.

Step 2. Identify the chords in the key.

Use the following charts to identify the scale degrees of the key you have selected. Replace the roman numerals with the corresponding notes in your key. The uppercase numerals on the outside of the circle will be your major chords. The lowercase numerals on the inner circle are the minor chords. The innermost ring will help you identify the diminished chord in your key.

*Please refer to the below image for an example. Make sure you are using the correct chart. if you are working on a major scale, use the chart on the left. If you are working on a minor scale, use the chart to the right.*

The above diagram is an example of the A major and F# minor scales as seen in the circle of fifths. When using the roman numeral formula to find the chords for each of these keys you will get the following result:

A major and F# minor are relative keys. This means that they share the same notes. The difference is that F# is used as the tonic or root note instead of A. Therefore, F# minor is the aeolian mode of the A major scale.

Once the chords are identified, it’s time to move on to the next step.

Step 3. Combine the chords

This is where the fun begins! Start with making a 3 or 4-chord progression. If you have your instrument handy, try different combinations of the chords you have identified and find something you like, then write it down. It’s fairly common in major keys to start the progression with the I chord and end on the V chord. This is known as an authentic cadence, also called a perfect authentic cadence. If you use this type of cadence, try different chords for the middle of the progression and see what you get. It’s fun to experiment! Also, keep in mind that there are other types of cadences, so try doing additional research on some of the other popular ones, if you’re interested.

If you’re looking for some inspiration to get the ball rolling, try some of these popular progressions:

To use these formulas, simply replace the roman numerals with the corresponding chords in your scale, just like you did when you identified the chords in the key you chose. To demonstrate, we will be using what is described as the commonly used progressions of all time, I - vi - IV - V. The following is an example of using this method in the key of A Major:

 

For better visual clarity, we have the chords that we plan to use highlighted.

Just as we can use the circle of fifths to identify our scale degrees, we can also use it to pick out the chords we need in any key if we have a chord progression formula in mind. This is also how you can use the circle of fifths to transpose to a different key.

Step 4. Play It!

Once you decide on a progression you like, play it until you are comfortable with the chord changes. If you aren’t familiar with the chords, it's always better to start slow and gradually build up your speed. Make sure the quality of your playing doesn’t suffer because you’re trying to rush. It’s always better to play slow and clean than to play fast and sloppy. This applies to any instrument. Of course, it’s always a good idea to use a metronome when you practice as well.

Step 5. Have some fun with it!

Once you get more comfortable with your progression, try different ways to play it. Try different rhythms and tempos. Maybe you could play each note individually (arpeggiate) instead of all at once. The possibilities are endless!

Bear in mind that this is just one way to create chord progressions. This article is intended to serve as an introduction to the basic concepts of music theory and the composition of chord progressions. If you’re just starting out, this is just the beginning! There’s so much to learn in the music world, and we want to help you on your musical journey! Please consider purchasing one of our circle of fifths posters from our online shop as your support will help us create new and better content for aspiring musicians. Thanks so much for reading! Until next time!