Section 5.3 How to Write Perfect, Major, and Minor Intervals
To write an interval above a given note, use the two methods given below.
If you are asked to write a minor sixth above the note \(\text{A}\), start with the \(\text{A}\) major scale and key signature. In \(\text{A}\) major, there is an \(\text{F}^♯\), which is a major sixth above the note \(\text{A}\). Therefore, \(\text{F}^♮\) is a minor sixth above \(\text{A}\).
Alternatively, you can simply count the number of half steps. If you know there are 8 half steps in a minor sixth, you can count from \(\text{A}\) up to \(\text{F}\).
Writing small intervals up to a major third below a given note is straightforward using a combination of whole and half steps. However, to write larger intervals below a given note, it is sometimes helpful to invert the interval first (Inversion of Intervals Explained is discussed in the next section).
