The circle of fifths is your friend. Then again, you could ignore it and just write everything in the key of C, like some producers. But that’d be like only using the preset EQ’s that your DAW comes with, without actually understanding any of them. It might not come to you the first time through this post, so re-read and play with the ideas, read other posts on the net, practice writing it out, and come back and re-read until you get it. It’s an incredibly important tool in music theory. It’s like setting up templates for tracks to improve your work flow.
The circle of fifths is the systematic representation of all major keys. It looks like this:
Last article we talked about how “keys” work. The circle of fifths is a systematic representation of those keys. It makes your life a lot easier, trust me.
It’s called the circle of fifths because it moves in fifths (or inverted 5ths, aka 4ths, depending which direction you’re going). For example, C is a fifth below G. G is a fifth below D, and D is a fifth below A, etc.
You should memorize the order of keys, in both directions. Here’s how I think of it: you always start with the key of C (no sharps or flats). If you want to figure out a key with flats in it, you go left, and start with F (because the word “flat” starts with “F”).
After “F” the keys are all flat (their root note is flat, like Bb) and they spell out “BEAD.” After BEAD, the last two keys in that direction are Gb and Cb. So for keys with flats, we get the pattern: C-F-Bb-Eb-Ab-Db-Gb-Cb.
And note that each of those keys goes up by one flat. C has no flats, F has one flat, Bb has two flats, Eb has three flats, all the way until Cb, which has 7 flats.
To go the opposite way, just flip that “F-BEAD-GC” pattern around, and sharp the last two keys. We get: C-G-D-A-E-B-F#-C#. Again, C major has no sharps, G has one sharp, D has two sharps, all the way until C# which has 7 sharps.
But how do we know which notes are sharp or flat? By two patterns called the order of sharps and flats.
Order of sharps: FCGDAEB
Order of flats: BEADGCF
Hey wait, isn’t that the same pattern as the order of keys themselves? Yep, it just starts at a different point. The circle of fifths has “C major” as its base, while the order of sharps starts on F, and the order of flats starts on B.
So, for example, say we’ve want to find out how many sharps E major has. We go to the circle of fifths and say, okay, E major is the 5th major key in the sharp pattern (C-G-D-A-E). Since C major has no sharps, the sharp pattern begins on the 2nd key (G). So G has one sharp. And each following key has one additional sharp. So, since E is the 5th key in the pattern of keys with sharps, it has 4 sharps. Then we look at the order of sharps and take the first four sharps to find out which notes are sharp in E major: F, C, G, and D.
Here’s another example: how many flats does the key of Eb have? Well, if we look at the circle of fifths, the flat pattern is: CFBEADGC. The key of Eb would thus be the 4th key in the flat key pattern. Thus, Eb has three flats. We can then look at the pattern of flats, and say, okay, this key has three flats, so the flatted notes will be the first three from the order of flats: Bb, Eb, and Ab.
The circle of fifths is hard to grasp at first, so don’t worry if you struggle the first time through. Re-read, check out other resources on the net, come back to it in a few days, or do whatever you need until you understand it. It’s an incredibly important foundation of music theory.
As always, if you have any questions or if anything was unclear, please comment and I’ll clarify. If you didn’t fully understand something, chances are someone else didn’t too!
TL;DR: The circle of fifths is incredibly important and can’t be “TL;DR”ed. Learn it. The order of “sharp” keys is: C, G, D, A, E, B, F#, C#. The order of “flat” keys is: C, F, Bb, Eb, Ab, Db, Gb, Cb. The order of sharps is: FCGDAEB, and the order of flats is: BEADGCF.