The Cycle of Fourths

It occurred to me earlier that I’ve spelled out the Cycle of Fourths in sequence from C, but I haven’t provided a picture of what it looks like yet. Here’s a brief summary and some links to more info, and for redundancy’s sake, here’s the sequence again:

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

And, here’s a picture of the Cycle, in all its glory. This is the one I’ve been referencing since I first blogged about it. Its the first image that comes up in Google when you search for “Cycle of Fourths”. Its originally from a guitar site called Deft Digits.

The Cycle of Fourths

Now, on to some info about the Cycle:

• Its alternately called the Cycle of Fourths or Circle of Fourths
• It includes all of the 12 notes in western music, from A to G, and thus has 12 positions, like a clock
• Instead of moving alphabetically, it moves in fourths, so (this is easiest to understand if we start on A – the 9:00 position):
  • If A-B-C-D is 1-2-3-4 then A is the 1 and D is the 4, so moving a 4th from A is D
  • If D-E-F-G is 1-2-3-4 then D is the 1 and G is the 4, so moving a 4th from D is G
  • If G-A-B-C is 1-2-3-4 then G is the 1 and C is the 4, so moving a 4th from G is C
  • If C-D-E-F is 1-2-3-4 then C is the 1 and F is the 4, so moving a 4th from C is F, etc.
• The first BEADG letters that appear are flatted (Bb, Eb, Ab, Db, Gb) and the next aren’t
• Later on, in music theory this lets people easily know the numbers of sharps or flats in a key, but I’m not ready for that yet
• Moving clockwise from one note to the next goes in fourths. Counterclockwise goes in fifths
  • If you pick a note (say, C) and move one note to the right (F), you’ve moved a 4th
  • If you pick a note (say, C) and move one note to the left (G), you’ve moved a 5th
  • Because of that, you can look at a note and its 2 closest neighbors and know where to go for a I-IV-V progression
    • If we start on C, then a I-IV-V progression would be C-F-G

Here are the two links I found most useful when I was reading about it a month ago:

• StudyBass: The Circle of Fifths Diagram (yeah, it starts with the Circle of Fifths, but just read it)
• Deft Digits: How to Memorize and Use the Cycle of Fourths