In western music there are three types of minor scales, the natural minor scale, the *harmonic minor scale, and the *melodic minor scale. The variety of minor scales gives the composer a larger range of notes to play with in a composition and is the reason I like to compose in the minor key.
To begin, let’s look at the most common western minor scale, the natural minor scale.
The natural minor scale is comprised of W-H-W-W-H-W-W where W is a whole step and H is half step. W is a major second and H is a minor second. If you look at the A scale above you will notice that there is no black key between the B and the C where a half step takes place. Similarly, there is no black key between the E and the F, where the other half step takes place. The 7 notes above comprise the A natural minor scale. Play the scale above and note the huge difference the minor third makes in the sound of the scale when compared to a major scale. Keep in mind that the minor scales can begin on any key. For example we can begin on the key of C.
Notice again the pattern of WHWWHWW. There is a single step between the D and the E flat, and a single step between the G sharp and the A flat. This is the natural minor scale starting on the key of C. The natural minor scales can begin on any of the notes on the keyboard giving you a multitude of different scales to play with.
Songs based on a scale play only the notes in that scale. For example, if we were composing a song based in the key of A natural minor, then we could use the following notes: A, B, C, D, E, F, G.
However, since there are two more types of minor scales, the *harmonic minor scale and the *melodic minor scale, we can use more notes by incorporating the other minor scales into the composition. Incorporating notes outside of the scale creates tension which can be easily relaxed because the minor scales are closely related to each other.