dissecting music

The circle of 4 or “of 4ths” is a handy tool when it comes to practice. It is inherent to a major part of harmonic progressions. Some people will be slightly confused when they hear this term though, because they are used to hear people talking about the circle of fifths. So, let’s clear up, what those terms actually mean and what the concepts can be used for. If the concept of an interval is unclear, read this.

What in gods name is all this circle of fifths nonsense!?

This is the circle of 4ths. It represents a movement throughout the 12 notes of our system by successive steps of perfect 4ths. But it is also the circle of 5ths – backwards. You see, every interval has a counter or mirror interval. For this thought experiment I’ll ask you to think of the 12 notes of our system as a wheel rather than a continuous tape – we don’t care about octaves right now. Just take the circumference of the circle depicted above. The counter interval is the one you have to add to any given interval to reach the point you started from again. In other words: Any interval put together with it’s counter interval adds up to an octave. For the sake of this experiment, let’s start from the note C by ascending (clockwise) a perfect 4th to the F. In order to get back to C now, we’d have to add a perfect 5th and go full cricle. The other solution would be to think of a descending 4th, leading back to the initial C.

So, descending a perfect fourth from any given note will lead you to the same note as if you’d ascend a perfect fifth. In the same way, descending a perfect 5th will let you land on the same note as if you’d ascend a perfect fourth. I refer to those two as mirror intervals. This is why the circle of 4 is the reverse circle of 5. If you move through the notes in ascending fourths you’ll get:

C F Bb Eb Ab Db Gb B E A D G C

by moving throught he circle in ascending fifths, you’ll get:

C G D A E B Gb Db Ab Eb Bb F C

So, now that this is clear – why are those so important? While other circles are important as well, only the chromatic circles of 4 & 5 will lead through all the keys while not moving in half steps (which would be the circles of b2 and 7). This means it provides a bigger and more holistic challenge for practice but there is one more reason why stuff should be practiced that way: To our ears, the circle of 4 is the most logical way for a chord progression to move. We’ll have a look on why this is the case later, but for now it isn’t really that important to know, so let’s cover the immediately applicable stuff first. Also I used the term chromatic when referring to the circle. This is very important as well, because of the way how the diatonic circles function is vastly different. We’ll get to this as well.
Are there any other uses for the chromatic C4? Yes there are – plenty.

The circle is also used for Modulation. Depending on what circle is used to modulate different emotional responses are evoked. Generally it is said, that a modulation up a perfect fifth sounds uplifting and exciting, while modulating up a perfect fourth is perceived rather soothing and relaxing. How modulations are perceived can be rather subjective though. So now that we know how the circle of fourths and fifths relate to each other I just want to add that while they are just two different faces of the same coin and serve similar purposes, in classical music people tend to rather talk about the circle of fifths. In contrast, the circle of fourths finds more use in jazz.

Let’s now talk about…

How to practice in CC4?

It is important to know all the arpeggios you use in various shapes, so that you can play them in any place on the fretboard. We covered this in the Guide to Arpeggios. Let’s now take a look on how those can be practiced efficiently, so you can get them under your fingers as fast as possible. Don’t wait too long before going one step further – you don’t have to perfect them. You’ll notice fast if the next step is too hard and can go back or you’ll adapt to the new level and get better.

One more thing: it makes complete sense to stick to practicing only two or three of those shapes if you have time constraints. Mastery of two shapes of the guitar is still pretty awesome and you can do pretty much the same, at least from a jazz standpoint. Just make sure the shapes you choose are adjacent to each other. I lay out the ways to practice and their uses pretty clearly in the following paragraphs, so just try to adapt your routines a bit. If you need help doing that, I’d be happy to assist. Here we go.

Step 1: CC4, always using the same shape

This is pretty easy. If you learn a new arpeggio take one of the CAGED-shapes and take it through the circle of fourths. You’ll change the key, by sliding up and down the fretboard quite a bit. The root will always change, but never the fingering. As you go trough the circle, always say the name of the key, you’re in – this will help you remember it’s position quickly. Play the Arpeggio ascending and descending as well as in asc. and desc. groups of 2, 3 and if you’re extra motivated 4.

This exercise isnt really good for anything other, than memorizing where you can find all the notes on the bass strings and for getting the arpeggios under your fingers. Don’t do this for too long – once you have memorized the shape, go to the next one. Once you have memorized all the shapes of an arpeggio go to

Step 2: CC4, connecting different shapes

This step is a bit harder but pays of quite well. The goal is to connect all the shapes so that you can switch between them fluently. Play all of them in succession up the neck, then modulate up a fourth and play them successively down the neck. Once you can do this, do the same thing, but alternate shapes between ascending and descending. Just make sure, that you play all shapes both ascending and descending while going trough the CC4. After a while you can go to

Step 3: CC4 in position playing

This is the final step. You should now have memorized (to some extent) all shapes of the chosen arpeggio in both ascending and descending direction. Also, all this training has made sure, that you know where you can find all the bass notes. In case you can’t play all of this without stopping and thinking now and then – don’t worry, that’s completely normal. Right now, we are working on getting your brain used to a certain coordination. It will take a few years to be really fluent doing that kind of thing. If you can pull it off fluently already – congrats, you’re a total badass.

Now it’s time to learn how to do all this stuff in position playing. Once you can do that, you’ll be able to play this type of arpeggio in the CC4 anywhere on the fretboard within a space of 5 frets. This is called position playing and is essential in jazz. The idea is, that you have to move the least possible to execute your music making operations.

This is a representation of the CAGED-shapes (hybrid shapes included) in the most logical order for a round trip through the circle of 4. In this case we stick to the lowest five frets on the fretboard, but this can be done anywhere really. You can start in any shape using any root, but practice the arpeggio of your choosing in this order.

In the next installation of this series, we’ll go one step futher, by applying what we just learned to actual music in the diatonic circle of 4. But first we’ll take a look on

Why do our ears hear in the Circle of 4?