Scales

Understanding the Circle of 4ths

The Circle of Fourths is a way for understanding relationships between key signatures.

The primary way to understand the circle of fourths is to see how scales progress from one to another. In short, the next scale is up a fourth from the current scale, and adds one more flat.

If we start on our C scale (with no sharps or no flats), and go up to the fourth scale degree of the C scale, we wind up on F. F will add a flat.

But which flat? Here’s where it gets great. Each new flat will also occur on the fourth scale degree. So in the key of F, the fourth is B♭ (which becomes flat in this scale). B♭ is not just the flat we add to the F scale, though, it’s also the next scale itself.

And B♭’s new flat (in addition to the existing B♭) will be E♭, which will be the scale after that, and so on.

This pattern continues all the way up to G♭ without any real issue. When we get to G♭ there are two important things to understand;

1. The fourth scale degree here - C♭ - doesn’t happen between C and B; it just becomes, enharmonically, the same as B (natural). 2. After G♭, we’re going to get into sharps. We could call the next scale C♭, but after that? Well we’d be getting into a bit of a mess - See the scale switch for more

So we have to decide at some point to switch from flats to sharps (and vice versa) in the circle of fourths. But why?

Well lets say we continued after G♭ with C♭. At this point, EVERY note would be flat – we’d have seven flats in our key signature with the addition of F♭!

(Worth noting, F ♭ is enharmonically the same as E (natural))

Now where would we go from here?

After C♭, the fourth scale degree would be F♭, which would be our next key. But everything’s already flatted, so what would we do to the key signature?

Well, we’d flat B a second time. Every other note would be flat, except we’d have B 𝄫 (enharmonically the same as A natural).

We could keep going like this as long as we wanted, but it’d just be getting silly quickly, as we eventually would pass the key of C𝄫 (with every note double flatted, and it's enharmonically the same as B♭ this whole time!) And then?

One Small Concession

Now we emerge in the key of B with five sharps in the key signature, which is not an easy place to begin parsing sharps. Enharmonically, it’s all the same as if we were going on into C♭, but taking the mental time to parse the key of B is worth doing.

From there? We just keep going up a fourth, to E. But we can’t have flats and sharps in the same key signature.

Taking away a sharp, though, is the same as adding a flat. So if we find the fourth of the key of E, then we “flat” it by taking away the sharp that was in the key of B (A♯) and have only four sharps. From there, we go up another fourth (to A, which we just un-sharped) and take away another until we’re all the way back to C.

Why those five sharps? What about going in the opposite order? AKA the Circle of Fifths

I’m glad you asked!

Let’s say we’re starting on the key of C and we’re trying to reverse-engineer our way the other way.

From C, to get to the first sharp key (and to continue from there) instead of going up by a fourth (which would add a flat and take us to F) we go up by a fifth to G.

Now figuring out our sharps from nothing isn’t quite as intuitive as the flats are.

Every time we add a new sharp progressing through the ‘Circle of Fifths’, it comes on the 7th (or second-to-last) scale degree. In the key of G, this would be F ♯.

Just like with flats progressing through the Circle of Fourths, we keep all our sharps once we have them. So a fifth up from G would bring us to D. We keep F♯ in the key signature and add the 7th scale degree for D (C♯). And on from there.

Similarly, we could stick with sharps for more keys than we do. A fifth up from B is F♯, and its 7th scale degree would be E♯. Instead, we shift to its equivalent, G♭.

Understanding the Circle of 4ths.pdf

Referencing the Sheet

The sheet we use also presents a second way to quickly remind yourself what is in a given key signature.

Circle of 4ths handout.pdf

1. First, identify the scale on the circle (not the concert pitch of the scale, but the scale you are playing on your instrument).

2. Just inside of the circle, you will see an indication of how many sharps or flats it has in a key signature. Remember, you can’t have both sharps and flats.

   • For the bottom three scales (D♭, G♭, and B) it lists the enharmonic equivalents as well. Use the inner ring for all three of these.

3. Using the inside of the circle, go through the order of flats/order of sharps (flats read left-to-right; sharps read right-to-left as the arrows indicate)

   • Sharps and flats always go in the same order. The first flat is always B♭ no matter what key you're starting in. It is absolute. The first flat in the key of G♭ is not G♭, it is B♭.

4. For any notes you’re unfamiliar with, use the enharmonic note ladder on the right to see their equivalent

   • Be careful in how you're considering these equivalents though…

     You have to be careful to not let it take the wrong place in your head. For example, in the D scale, if you were to think D, E, G♭… then it would only be natural to skip over G next and go right to A. It's not guaranteed to break your mental conception of the scale, but be careful!

5. To give your eyes something to track along with, the musical alphabet at the bottom is helpful. Just make sure to keep track of everything in your key signature as you do so.

Wow, the Circle of 4ths is MAGICAL! How can I spend more time with it?

15-minue video

Interactive site that doesn’t include key signatures?

More than you ever wanted to know about it including modes

To help you work on keeping your key signatures straight: Music-Theory Net Practice Pages

Rhythm Assessment Strategies

• Ensure you understand how to properly clap and count the rhythms
  • Make sure your pulse is consistent; that’s what the clapping is for
  • If you find places where you regularly need to slow down or get confused, reference the rhythm assessment recordings
• Write in the counting for any particular beats/measures you struggle with
  • Reference the recordings for these