IB Course Entry, Music: Modes and Cadences

Music, after all, is just a collection of sound frequencies produced by instruments or speakers that enter our ears. How does music make us feel? How does it make us feel happy, sad, angry, or annoyed?

During our course of IB Music, we learned about musical cadences and modes. Musical cadences is a change in music intervals at the end of a phrase. They are like small conclusions. When you hear the end of a verse or chorus, you are hearing a cadence. Modes consist of major and minor modes, as well as other complex ones.

In music class, we are required to interpret cadences and modes both from looking at them on music, and hearing them. The interesting thing was that these cadences and modes could be interpreted into emotions. The minor mode, for example, conjures a very sad and melancholy emotion, while the major mode often generates a happy and cheery feeling.

There is a similar concept with cadences. The picture above consists of four types of cadences we learned in music class: authentic cadence (or perfect cadence), half cadence (or imperfect cadence), plagal cadence, and deceptive cadence (also called surprise cadence). Each of these cadences, no matter what key they are in, generate a different feeling of conclusion to the end of a musical phrase. Cadences are very mathematical. The authentic cadences is the movement of I - V - I , which means the chord of the first note of the scale, the fifth note of the scale, then back to the first (example: in C major: C major - G major - C major). The result is a conclusion that sounds like a perfect end to a song. Returning back to the tonic (I, first note of a scale), makes us feel that the song is very complete.

The plagal cadence is also called the "Amen cadence," because it is often used in church songs and hymns (I - IV - I). The very familiar "Ah~men" at the end of any generic hymnal song is actually a plagal cadence. The result is a holy and concluding finish.

The deceptive and half cadences both sound unexpected. They both surprise us, because it appears that they will return back to the tonic (first note of a scale). But it doesn't. The result is that listeners are surprised. Many composers use this strategy in their pieces.

Below is a Youtube video showing audio examples of cadences.

I thought it was amazing that frequencies and maths of music can generate emotions in people. I think this relationship is something I'd like to investigate in more in the future.