Firstly, for all piano students out there studying Counterpoint, this is the easiest species to study.
In general, Piano teachers don’t foster the study of Counterpoint to their students, and focus only on the technique, the expression and the stylistic approach of the pieces; but for the most advanced students, knowing the notes is not enough and that is when they should start other studies that they have more to do with the “Grammar” of the music.
In the case of the fourth species, we are dealing with suspended notes that momentarily become dissonances against the Cantus Firmus” (CF from now) and then resolve a note down to the safety of a consonant interval to re-establish the balance in the melodic line.
Why is this the easiest of all the species?
Very simple, because the rules that we have to apply are minimal:
-There are three stages in this species: preparation, suspension and resolution.
-all the preparation notes have to be consonances. As they are prolonged to the next strong beat, they become a dissonance, and they should be resolved a tone or semitone down to a consonance.
-If the suspension is not a dissonance against the CF, it can go by step, skip or leap up or down this note.
What is challenging is to produce a balanced and beautiful melodic line without sounding formulaic; This is often achieved by stopping the species momentarily and use the second species to bring some changes, preventing the melody from sounding dull or uninteresting for the listener.
By the time you can control the 4th species, you will be free to plunge yourself into the last and 5th species, in which, with lots of crafty patience, you will be able to create unique melodies, using and combining all previous species.
Click on the link aforementioned to access to the full post, and also to the different Species analyzed by Gisela Paterno!