Circle of Fifths - Cycle of Fourths
Understanding the natural progression of scales in contemporary Jazz and Classical styles is a key to song writing and can also be used in practice.
This image of the circle of fifths / cycle of fourths is reversed to most you will see. The Cycle of Fourths runs clockwise and the Cycle of Fifths runs anti-clockwise. It still all means the same this and is created in the same way. Notice as we cycle through the fourths that a flat is added on that side of the image. When practicing or writing in a contemporary or Jazz style it can be handy to cycle your chord progression around in the fashion of the cycle of fourths. Alternatively, you can go the other way for a more classical style. How many songs have been written with a chord progression that goes C - G - D and then the occasional A. You’re probably doing it and don’t even know why.
When you circle through the fifths what you are doing is starting the next Major Triad or scale on the Fifth increment of the previous. If you want a Jazz feel go the other way and play the fourth increment.
An easy way to remember the cycle or the circle is to know that the keys (without incidentals) are C at the top, F then BEAD G BEAD G in the direction of the cycle of fourths. The first BEAD G is all flat and the second is all natural.
