LESSON 2.
BACK TO LESSONS
LESSON 1
THE CIRCLE OF FIFTHS
Why some scales have sharps in the key signature and others have flats?
Lets analyse the organisation of ascending C major scale after adding high D which is just natural
supertonic (2nd step) of this scale:
If we compare an organisation of the steps in I and II part of the scale, they appear identical. Using
this principle we can built another major scale from the 5th degree (dominant - G) of the present
scale:        G major scale        G~A~B^C~D~E~F+^G
On the 7th degree of this new scale sharp sign appears (F sharp) which becomes key
signature
of this scale:
Now, the creation of subsequent ascending scales using the same principle results in the following
major scales with the sharp key signatures:
We can't create more major scales in ascending direction because of the rule of diatonic construction
which dictates that the next letter of the alphabet be used in sequence. But we can still create major
scales in descending direction using the same principle of adding a note as before. Lets start with
descending C major:
If we compare an organisation of the steps in I and II part of the scale, the difference only is in the
half step between low C and B. The creation of the new F major descending scale requires whole step
between C and B, which is B flat. Using this principle, we will have F major scale with one
flat in the
key signature:
Now, the creation of the subsequent
descending scales using the same principle
results in the following
major scales with
the flat key signatures:
Now if we put C major (no sharps no
flats) on the top of the imaginary
circle, appears that the keys of the
major scales are arranged clockwise in
ascending fifths as the number of
sharps is increased by one in each
succeeding scale. Counter - clockwise,
the keys of the major scales are
arranged in descending fifths as the
number of flats is increased by one in
each succeeding scale:
There are 15 major scales and 3 of them are enharmonic scales (identical in sound but are called by
different letter names: B  C flat; F sharp G flat; C sharp D flat).
So in general we have got 12 major
scales:
LESSON 3
to lessons