The Major Second interval, also called “full step”, could be called the main raw material for singing the Mass. We will see how often we use it. Below is a short video tutorial on how to play a major second on a keyboard, but if you can sing DO-RE-MI in tune, you know the major second: DO-RE is a major second, and so is RE-MI…

These greeting tones from the Roman Missal are EXCLUSIVELY constituted with Major Second intervals:

So is the “Orate Fratres” of the Roman Missal :

…and so are the tones for the concluding rites: