music theory for musicians and normal people by toby w. rush
The Minor Scales
There are actually two things that define a key:
the key signature is the most obvious one, but
another important part of a key is the tonic...
œ
œ
œ
the note around which the key centers.
& œ
œ
œ
this key is defined
œ
œ
by a key signature
of no sharps and
flats, but also by
the fact that it
centers around c.
but what if we change the tonic? what if we use the same notes for the key signature,
but change the note that the key is centered around?
œ
œ
œ
œ
if we center the key around the sixth scale degree of the major scale,
œ
œ
œ
we get a new scale: the minor scale.
& œ
the whole step
the thing is, common practice period composers
here didn’t have
weren’t all that crazy about this scale, because
the tension
it lacks something the major scale has:
they liked going
a half-step from seven to one.
into the tonic!
œ
œ #
œ
so here’s what they did: they raised the leading-tone by a half-step with
œ
œ
œ
an accidental. This gave them the tension they were looking for!
œ
& œ
this scale is great for building chords, so we refer to it as the harmonic minor scale.
however, composers didn’t use it for writing melodies, because it had a problem:
an augmented second between the sixth and seventh scale degrees.
so, for melodies, they made another change:
now we only
œ
œ #
they added another accidental to raise
have whole steps
œ #
œ
œ
the sixth scale degree by a half-step .
and half-steps!
œ
œ
& œ
œ
œ N
œ N
œ
œ
œ
œ
œ
&
now, remember... the reason we raised the leading tone in the first place was to create
tension from the seventh scale degree to tonic. but in a melody, if the seventh scale
degree is followed by the sixth scale degree, we don’t need that tension, so we don’t
need to raise the leading-tone at all.
the way we illustrate this is by differentiating between ascending melodic minor and
descending melodic minor; for descending melodic minor, we don’t raise anything!
licensed under a creative commons BY-NC-ND license - visit for more