We have already seen the major scale and how it is constructed. Now it is time to talk about another important scale: the minor scale. In fact, there is not just one minor scale, there are three.
The natural minor scale
The natural minor scale is the “original” minor scale and the foundation for the two other minor scales.
The interval formula for this scale is: W H W W H W W
As always, W means a whole-step and H is a half-step.
If we choose the note C as our starting point and apply this formula, we get the scale of C minor: C D Eb F G Ab Bb C
Explanation: C to D is a whole step, D to Eb is a half-step, Eb to F is a whole-step, F to G is a whole-step, and so on until we have reached another C.
Contrast this with the scale of C major: C D E F G A B C
They have four tones in common — C, D, F and G — but three tones are flattened in the minor scale: Eb, Ab and Bb.
The same is true for all natural minor scales, so there you have another method of forming the natural minor scale: you take a major scale and lower the 3rd, 6th and 7th tones.
Let’s do that on the scale of E major. If you’ve practiced your major scales, you know this is: E F# G# A B C# D# E
Now lower the 3rd, 6th and 7th tones: G# becomes G, C# becomes C and D# becomes D.
The scale of E natural minor is then: E F# G A B C D E
The two other minor scales — harmonic minor and melodic minor — are both derived from the natural minor scale. Let’s look at the harmonic scale first.
The harmonic minor scale
This scale is almost identical to the natural minor scale, except for one tone. I could give you an interval formula for the harmonic minor scale, but the following rule is much easier to remember:
Harmonic minor scale = natural minor scale but with #7
In other words, the only different tone is the 7th, which must be sharpened.
Let’s make the harmonic scale of C minor. We’ve seen that C natural minor is: C D Eb F G Ab Bb C
The 7th tone in that scale is Bb. If we sharpen this tone (raise it by a half-step), it becomes B.
Then the harmonic C minor scale is: C D Eb F G Ab B C
That’s all there is to it. Now you’re probably wondering: what is the purpose of this harmonic minor scale? It has something to do with chords (as its name implies).
We haven’t discussed this yet, but you can build a chord on each tone of the scale. If you build a chord on the 5th tone of the natural scale of C minor then it would be a G minor chord consisting of the tones: G Bb D
However, in a lot of music this so-called 5-chord (or V-chord in Roman Numerals) sounds better as a major chord or a dominant-7 chord, and the chord G major consists of the tones: G B D
To make this possible, the tone Bb must become a B. Playing the 5-chord with a “major” sound is important enough that the musicians of the past thought it warranted the use of a new minor scale: the harmonic minor scale.
If that went way over your head, don’t worry. Just remember that the harmonic minor scale is the same as the natural minor scale, except for the 7th which must be raised.
The melodic minor scale
We’re not done yet. If you look at the harmonic scale of C minor — C D Eb F G Ab B C — you’ll see that there is a big gap of 3 half-steps between Ab and B. That big jump doesn’t sound so good in melodies.
To fix that, another scale was introduced: the melodic minor scale. It’s the same as the harmonic minor scale but with the 6th tone raised a half-step also.
The melodic scale of C minor is then: C D Eb F G A B C
As you can see, this is almost the same as the scale of C major, except for one tone: Eb
So now you have three ways to create the melodic minor scale:
- Take the natural minor scale but #6 and #7
- Take the harmonic minor scale but #6
- Take the major scale but b3
As you can guess from its name, the melodic minor scale is often used for… melodies.
There is one complication: in classical music, this scale is used only when the melody goes up but notes going back down use the regular plain-old natural minor scale. This is not a strict rule, and is much less applied in contemporary music, but still something to be aware of.
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