Keys Change
Music does not need to stay in one key; key changes happen frequently in pieces of music. The way that you will learn to change keys and identify key changes will become much clearer when you understand harmony more. For now, you can go back to the circle of keys and simply make a few assumptions that will be explained as the book progresses.
Here are the rules:
When music changes keys, it does so to a closely related key.
The closest related key is the relative minor.
The other close keys that you can modulate to are next to the original key on the key circle (either one key to the left or one key to the right).
The other modulation you can make is from a major to a parallel minor; for example, C major to C minor.
Talking about “common” and “simple” ways to change keys does not mean that the more difficult and uncommon ones are not used; just the opposite is true. Composers love to break the rules and find interesting and musically compelling ways to do so. Part of learning about theory is understanding what the majority of music did when it was written — what were the norms of the times and why did the composers use them? There will always be musicians who push the boundaries of music, bringing music to new levels.
Keys are more than just scales and key signatures, so you really need to keep moving on into the rest of the scales and chords and harmony to fully grasp what keys mean and how you will use them. For now, you have the basic groundwork that you need in order to name and spell keys, which was your goal for this chapter. The next step is to look at the last group of scales and modes that you will deal with in this book, and then on to bigger things: chords and harmony!
