Music Notation Basics Part II - Key Signatures & Accidentals
(28 Oct 04)
In Part I we covered the idea of modifying the natural notes by using the sharp and flat operators, or accidentals as we called them. You will often see a number of accidentals immediately to the right of the clef symbol, although sometimes there are not any at all. The set of accidentals that you see next to the clef is called the key signature. Shown below are three examples. This is what we will cover next.
If you do not know how a major scale is defined, no problem. In that case, I recommend you look at Guni's Chord Scales series of articles though, because so many aspects of music theory begin with the major scale, and can be easily remembered by using it.
For now, just know that the notes of the C major scale are as follows:
C D E F G A B
There are no sharps or flats in this major scale, and in Part I you learned that these notes are called the natural notes. When a piece of music is written using just these notes, musicians say the music is written in C major, in the key of C or simply "in C". All phrases mean the same thing.
Since the key of C has no sharps or flats, its key signature has none, either. A piece of music written in the key of C will have no accidentals at all immediately to the right of the clef.
The C major scale is a great starting point for creating the remaining eleven major scales. A common way to do this is to write out the notes of C major, beginning with C just as I did above. Then, follow two simple rules to create the rest of the scales. The rules come from what is known as the Cycle of Keys. There are actually two cycles of keysone is the cycle of fourths, the other is the cycle of fifths. We will use one cycle to create half of the major scales, then the other cycle to complete the other half.
Creating the Major Scales from C Major
Begin by writing down the notes of C major:
C D E F G A B
We will create the first half of the twelve major scales by following two simple steps. First, re-write the previous major scale (in this case, C major) beginning on the fifth note of that scale:
G A B C D E F
Next, sharp the seventh note of the new scale:
G A B C D E F#
You have created a new major scale, G major. Notice that G major has one sharp note. The key signature used to show that a piece of music is in the key G is shown below.
Notice that this key signature is a) immediately to the right of the clef, and b) has one sharp accidental on the line of the staff that represents the note F. Pretty simple--so let's do it again.
This time though, begin with the new G major scale as our starting point. We will follow the same two-step process, first by writing the scale beginning with the fifth note, just as we did with the C major scale:
D E F# - G A B C
and finishing by sharping the seventh note of the new scale:
D E F# - G A B C#
This is D major. Here is the key signature for D major.
Notice that the D major scale has two sharps (F# and C#), and that the key signature has two sharp accidentals on the staff, one on the 'F' and one on the 'C' space.
Notice the order of placement of the accidentals in the key signature. From left to right, they are in the same order they are appearing as we create our scales. Repeat the process we just completed, but begin this time with the D major scale. Again, first step is to rewrite it beginning on its fifth note (A). The second step is to sharp the seventh note of the new scale (in this case F). THe result is A major:
A major: A B C# - D E F# - G#
Repeating this simple process two more times produces E major and B major:
E major: E F# - G# - A B C# - D#
B major: B C# - D# - E F# - G# - A#
Let's stop at this poit and notice the order that we gathered sharped notes as we made the major scales. They appeared in the following order: F#, then C#, then G#, D# and A#. Here is the key signature for our final scale, B major.
Sure enough, the accidentals in this key signature come in the same order, read from left to right.
At this point we have created five new major scales, beginning with C major, choosing the fifth note as the new starting point, and sharping the seventh note of the new scale. That was making use of the cycle of fifths I mentioned. Before moving on to create the remaining major scales, let's make a note of something useful. The last accidental that appears in all of the above key signatures is one half-step below the note name of the key itself. So for example, the last sharp to appear in the key signature for A major is G#. G# is one half-step below A. For B major, the last sharp to appear in the key signature is A#, which is one half-step below B. This fact will help you quickly recognize the name of a key from its key signature.
Now, we are going to being with C major as our starting point again, but this time we will apply a different two-step process, based this time on the cycle of fourths. As always, we begin with C major:
C D E F G A B
Step one is to re-write the previous scale, but beginning on its fourth note:
F G A B C D E
Step two is to then flat the fourth note:
F G A Bb C D E
Voila! There is our sixth new major scale, F major. Here is the key signature for F major.
So, the key signature for F major shows a single flat, surprisingly enough, on the line of the staff that means B.
I'll do it just one more time, so you can do the rest yourself. Remember the stepsfirst take the previous scale and re-write it beginning on its fourth note:
Bb C D E F G A
then flat the fourth note of the new scale:
Bb C D Eb F G A
The new scale is Bb major. The new flat is Eb, and so you will expect a new accidental in the key signature, on E, just to the right of the flat that is on B.
Continue this process until we have little left to do, and you will create all the remaining major scales, in order:
Eb major: Eb F G Ab Bb C D
Ab major: Ab Bb C Db Eb F G
Db major: Db Eb F Gb Ab Bb C
Gb major: Gb Ab Bb Cb Db Eb F
I stop here because the next step would be to create a scale that looks like this:
Cb Db Eb Fb Gb Ab Bb
If you rename each of these notes using their enharmonic names (discussed in Part I), you will see that this scale is exactly the same as one that we have already created. The key signature for the last scale we made above, Gb major is shown below.
You can check for yourself to see that these accidentals appear, from left to right, in the same order they appeared as we built our major scales. We had a little 'trick' for identifying the name of a key from its key signature for the major scales that contain sharps, and we also have one for these major scales--the ones containing flats. The next-to-last flat that appears in these key signatures has the same name as the key itself. You'll just have to remember what F major looks like--it only has one flat!
The pattern of sharps or flats that appear in each key signature are standard and never change. When key signatures are shown with other clefs, such as the bass clef, they are simply shifted up or down so that they are positioned correctly over the lines and spaces of the staff. The left-to-right pattern remains the same regardless of clef.
Finally, the figure below depicts a mnemonic I use to help me remember the relationship between the number of sharps and flats in a given key and what order the key comes in when the major scales are created the way I just showed.
In the figure above, I've listed the names of the major scales from top to bottom in the order we generated them using the cycle of keys. Then, a horizonatal line separates the scales into two groups: C major and all the scales having from 1 to 5 sharps appear above the line, and all the scales having from 1 to 6 flats are shown below the line.
Also notice the pair of braces to the left of the list of scale names. These braces highlight the ordered sets of scales whose names begin with B, E, A, D and G. I find 'BEADG' easy to remember, and useful. You can relate these ideas to the number of sharps or flats you see in a key signature until your recognition is automatic. If you find it hard for this to become automatic because you don't spend that much time with music, you have a scheme to fall back on, and you know where the scheme comes from.