The 'Circle Of 5ths' is a simple representation of the flats and sharps in a key signature. The following is a simple chart to learn:
C-no flats
F-Bb
Bb-Bb Eb
Eb-Bb Eb Ab
Ab-Bb Eb Ab Db
Db-Bb Eb Ab Db Gb
C-no sharps
G-F#
D-F# C#
A-F# C# G#
E-F# C# G# D#
B-F# C# G# D# A#
If you don't understand this layout, the letters on the far left are the key the rest of the sharps and flats are in. In the key of C, there are no sharps, and no flats. In the key of F, there is one flat, and that is Bb (and so on and so forth).
You may begin to notice a patter in the notes, and yes, you are seeing a pattern. It goes like this: B E A D G C F, and repeats itself numerous times. It is read from left to right for flats, and right to left for sharps. This is a good way to memorize the 'Circle Of 5ths'.
You may not completely understand where the flats and sharps come from. If you know anything about scales, this will not be too difficult for you to understand. If you, however have no idea what i'm talking about, you had better go to a more basic lesson.
The sharps and flats of the circle of 5ths are derived from the scales of certain notes, which also determine chords and the key signature of music. Basically, in the pattern of notes, a scale begins with the first of the scale (also the 8th), and works it's way up in this order:
Whole-step, whole-step, half-step, whole-step, whole-step, whole-step, half-step.
A 'whole-step' is the distance between two notes that are not flat or sharp. A 'half-step' is the distance between that note, and it's sharp version (which would be named also as the flat of the note following). Here is an example along with a listing of the notes to be divided into a scale in order (the star stands for the start of the notes, and the w stands for a whole step, and the h for a half step according to where the star is positioned:
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
* h w * h w * h w * h w *
Do you understand now? You may have noticed that the space between E and F, and B and C is only a half step. This is true to the nature of these notes, and therefore, you must be careful of how you divide your notes to make a scale. Now we can make a scale.
We will start with the scale of C. There are seven notes in a scale before it reverts back to the first of the scale. Once again, the pattern for writing a scale is whole-step, whole-step, half-step, whole-step, whole-step, whole-step, half-step. So we begin at C (with the star):
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
*We must then move one whole step to find the second note in the scale:
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
* h WSo the next note in the scale is D. So far we have C and D. We then have to move another whole step as the pattern suggests:
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
* h W h WAnd from this we derive the next note is E. We now have C and D and E. The next step is to move one half step:
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
* h W h W HAnd because E and F are only one half step apart, our next note is F. So far we have C and D and E and F in the scale of C. Using what you have learned so far, we can determine that all the notes in the scale of C are C D E F G A and B. You might notice that in the scale of C, there aren't any flats or sharps. This, you might also notice, is the same for the notes in the Key of C in the 'Circle Of 5ths'.
That is how they 'Circle Of 5ths' works. I'll do one more example for you so you can get a better idea. We will this time do the 'Scale of Ab':
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
*Like before, we can find the second note of the scale by moving one whole step. This may seem difficult because we have reached the end of our notes, but don't worry, because they continue on in the same order. Think of the last note as being the same as the beginning note, because they are both A. Here is what happens:
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab A
h W * h
Both the A at the end and the A at the beginning counted as a half step because they are the same distance, just copied twice to suggest the notes continue. Our second note after moving a whole step is Bb. You may wonder why it is Bb and not A#. This is because the note before it on the scale is an A. Two consecutive notes on a scale should not be the same letter note, so therefore, it is transcribed as a Bb because there was an A before the B.
Continuing with the scale, you will find that the notes of the scale are:
There are four flats in this scale, and also there are four flats in the key of Ab in the 'Circle Of 5ths'. The flats are also the same notes as the flats in the 'Scale of Ab'. You can make any scale with the whole-step/half-step pattern by beginning with the note you want the scale to be.
Another thing on the 'Circle Of 5ths' you might notice if you study it deeply, is there are some keys that are the same. These keys I have not listed above, but I will explain them to you.
These keys are called 'Enharmonic Equivalents', which means they are named differently, but are still the same key. However, you might not be able to tell right off the bat, because the notes are named differently, yet they are the same pitch and therefore, you use the same frets on the guitar (for example, Ab is the same as B#). They are:
C#- F# C# G# D# A#
Db- Bb Eb Ab Db Gb
F#- B# F# C# G# D# A#
Gb- Bb Eb Ab Db Gb Cb
B- F# C# G# D# A#
Cb- Bb Eb Ab Db Gb
As you can see, the pitches of each coinciding key match up to a pitch of the other. That is the basic holy 'Circle Of 5ths'. If you have any problems with it, or would like to see something added, please let me know!
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