Understanding the Cycle of Fourths and Fifths

Okay, here's the diagram we've provided for you. It shows the cycle of fourths and fifths.

The Cycle of Fourths

As you move around the cycle of fourths, that is, to the right, you get:

• C
• F
• B flat
• E flat
• A flat
• D flat
• G flat

You're moving in fourths, and with each new key, you add another flat. We will see that in a moment.

The Cycle of Fifths

Going around this diagram in the opposite direction, we have the cycle of fifths where you add sharps. The sequence is:

• C
• G
• D
• A
• E
• B
• F sharp

At each point, for instance, G has one sharp, then D has two sharps, and so on.

The Same Pitch

When we get to F sharp (or G flat), those are actually just two words for the same key on the piano, meaning the same pitch.

Key Signatures

This chart shows you the actual key signatures. You can see that every key maintains a constant relationship between its tonic note and all of the intervals in the key by adding flats and sharps.

Triads and Roman Numeral Notation

Here is a chart in three keys of triads. Underneath each triad is a Roman numeral. This notation describes chords in relation to the scale degree on which they are built:

• Small letters indicate minor
• Capital letters indicate major

Key of C Triads

The first line in the key of C goes:

1. I (1)
2. ii (2)
3. iii (3)
4. IV (4)
5. V (5)
6. vi (6)
7. vii° (7)

And then it circles back to I again, allowing you to see which ones are major and minor.

To reinforce the concept of transposition, I've also provided it in F with one flat, and G with one sharp.

Triadic Intervals

Here's the same thing again, but with an added seventh:

• The triadic intervals are: 1, 3, 5.
• By skipping to the next odd number, we include 7.

Once again, this is presented in three keys, and you would really do well to practice this in every key. If you have a keyboard, this will really increase your facility faster than almost anything I can think of concerning being able to grab chords.

Chord Symbol Guide

Here is the chord symbol guide. There are even more ways of representing chords, but you can see:

• Simple abbreviations like major and minor
• Graphic signs like the circle, the circle with a line through it, and the plus triangle

These are all attempts to represent chords in the most compact way possible, so that it's easy to put them onto lead sheets.

Practical Advice

This material is pretty self-explanatory; however, it might be a good idea for you to print it out. Keep it to one side in case you're reading through some music that contains some of these symbols. This way, you'll become familiar with them and be able to refer to this guide easily.