The Circle of Fifths is based on the perfect fifth interval.
The diagram below is an example. You can start with any note,
the next note is the perfect fifth of that note (seven half steps).
In the case of the C note the next note is the G note (seven half
steps), the perfect fifth of the G note is D, that is the next
note on the circle of fifths. Continue this process in a clockwise
direction and you have the circle of fifths. Seven half steps
can also be seen as three whole steps and one half step. The reason
for using whole steps is that scales are made of whole steps and
half steps.
To help understand the concept of a perfect fifth, D is the fifth
note of the G scale, G is the fifth note of the C scale, C is
the fifth note of the F scale, and so on through the Circle of
Fifths.
There are many uses for the Circle of Fifths.
The order of sharps and flats.
Sheet music key signatures.
The three primary chords of any key.
Basic chord progressions.
Transposing songs.
My suggestion to help you make use of the circle of fifths is
to first analyze it's construction. Memorize the sequence of letters:
"BEAD GCF", forwards and backwards. The circle of fifths is constructed
as follows:
The circle is like the clock, 12 positions just like 12 hours
on a clock.
The key of C is at the top center like 12:00, no sharps no
flats.
The phrase BEAD GCF runs counter clockwise twice around the
circle.
Notice on the circle the top starts at no sharps or flats
and the number of
sharps and flats increase as they head towards the bottom center.
Sharps on the right, flats on the left.
At the beginning of a song their is usually a series of sharps
or flats that define the key of the song. This series of sharps
or flats is called the key signature and they follow
a specific order. The order of sharps follows the Circle of Fifths
in a clockwise direction starting with F. That means that if a
key has one sharp, that sharp is F#. Two sharps would be F# and
C#. Three sharps F#, C#, and G#. The order for sharps is F#, C#,
G#, D#, A#, E#, B#. The order of flats follows the Circle of Fifths
in a counter clockwise direction starting with B. If a key has
one flat, that flat would be B flat. Two flats would be B flat
and E flat. Three flats B flat, E flat, and A flat. The order
for flats is B, E, A, D, G, C, and F.
The key signatures follow the Circle of Fifths starting with
C. The key of C has no sharps or flats. The key of G has one sharp,
the key of D has two sharps, the key of A has three sharps and
so on around the Circle of Fifths. The key of F has one flat,
the key of B flat has two flats and the key of E flat has three
flats and so on around the Circle of Fifths.
The three primary chords of any key can be determined quickly
from the Circle of Fifths. For example, the three primary chords
for the key of C are C, F, and G. The three primary chords for
the key of G are G, C, and D. The key has each of its primary
chords on each side of it in the Circle of Fifths. The three primary
chords consist of the root, the perfect fourth and the perfect
fifth.
The circle of fifths diagram also displays the relative minor
keys in the inner circle using lower case letters. For the key
of C the relative minor scale is A minor. They are relative because
the key of C contains the same notes as the key of A minor. The
key of C = C, D, E, F, G, A and B and the key of A minor = A,
B, C, D, E, F and G.
Basic chord progressions and song transposing will be covered
in another lesson.
