Being able to form scales from pure intervals is a common and useful way to spell scales. Another convenient way is to derive them from major scales. Many students become comfortable with spelling major scales and find it easy to recall them. If you look at the difference between a major scale and a minor scale with the same root, you can form another way to spell minor scales: deriving them from modifications to the major scales. FIGURE 4.7 shows a C major scale on the top line and a C minor scale on the bottom line.

FIGURE 4.7 Major and Minor Scale Differences

The scales are very similar. The notes C, D, F, and G stay the same. Only the third, sixth, and seventh note are changing from the major scale to the minor scale. More specifically, the third, sixth, and seventh scale degrees are lowered exactly one half step from their spelling in the major scale to make the minor scale.

Since you have dealt with intervals in detail, take a closer look at what happened when you went from the major scale to the minor scale. Simply, the intervals of the major third, major sixth, and major seventh (when measured from the root of C) are all changed from major intervals to minor intervals simply by lowering each of the intervals one half step. Remember from the discussion of intervals, the only difference between a major interval and a minor interval is that the minor interval is one half step smaller than the major interval, or vice versa.

This means that any major scale can become a minor scale by lowering the third, sixth, and seventh scale degrees one half step. This method derives the minor scale from the spelling of the major scale—using the derivative approach. This is one more way to look at spelling the minor scale. It is important to be comfortable with all the different ways to spell scales because you never know which one will work the best for you!