Secondary Triads, Stable and Unstable Degrees (Lesson 6)

During the previous lesson we stopped at chords of main (or stable) notes of the tonality. In this lesson we will try to find out, what are the chords of unstable degrees, or secondary triads, how are built and what for do we need them.

Triads, which are built on 2nd, 3rd, 6th and 7th degrees are called secondary, as they are of secondary importance in the tonality. So, on each degree except 1st, 4th and 5th we can build these so-called secondary triads.

If you are conscious enough, try to build these chords in those tonalities, which you already know: C major, G major and F major. Let me remind you, that the chord may contain only the notes of the certain tonality. So, in C major all chords will be build on white keys, in G major instead of F you should us F sharp, in F major there will be B flat instead of B.

After spending some time (not more than 10-15 minutes) on this, you`ll come to following conclusion:

  1. Secondary triads on 3rd and 6th degrees have the opposite colour (minor triads in major tonality and vice versa)
  2. On II  degree (supertonic) and VII degree (subtonic) can be done two triads – one with the opposite harmony and another – a diminished one. This is for major tonalities, and what happens in minor tonalities I`ll tell you next lesson.
Triads in G, C and F major

Triads in G, C and F major

So, different triads of the tonality sound different. And it depends on what degrees are there in the triad. This is like how your mood forms. It is a sum of all your smallest feelings, impressions and wishes at the certain moment. And if some of these feelings and emotions change, your mood in general will also become different, won`t it?

For instance, you got to a meadow in blossom, you enjoy sunny weather and motley flowers, hear, how insects buzz etc. But suddenly the sunshine becomes too bright for your eyes, you feel hot and want to drink. And if you put on a hat or drink some cold water – everything will change for the better.

The same situation is in music – the unique sounding of this or that accord depends on each its sound. So the stability of each triad directly depends on how many stable and unstable degrees in it.

We`ve already met these terms during our previous lessons, when we talked about stable degrees and turns. Now I`ll try to give some more information.

In any tonality different sounds are less or more stable and have different levels of affinity to other sounds. For example, the 1st degree – the tonic – is the most stable sound of the tonality. In a musical composition tonic gives an impression of buttress and satisfaction.

The 2nd degree is unstable, and a person, who hears it, wants some continuation or conclusion. And it is possible, when after the 2nd degree or supertonic comes the tonic. This is resolution.

According to the level of stability sounds may be placed in the following way :

  • I degree – the most stable degree without affinity;
  • II degree is very unstable and is attracted to the tonic;
  • III degree is rather stable and almost doesn`t lead to any other degree;
  • IV degree is unstable and is attracted downstairs;
  • V degree is stable and almost doesn`t have any affinity;
  • VI degree is unstable and has mild affinity downward towards V degree;
  • VII degree is the most unstable sound in the tonality and has huge affinity upward towards the tonic.
Stable and unstable degrees

Stable and unstable degrees

This classification is rather subjective and may sound a little bit different for various people and in various tonalities, but the general idea is the same. Anyway, no one argues, that I, III and V degrees are stable.

So the tonic triad, which consists only of stable sounds is the most stable in the tonality. Now you can classify all the triads according to their stability. You can guess, why the triad of III degree is more stable, than the triad of VI degree, can`t you?

The process of creating music, both its melody and harmony, comes down to two things – you make intensity (instability) and resolve it. That`s why those, who listen to your music are interested in it, and they look forward to hearing it again and again.

Let`s try to feel all the aspects of this intensity/instability through an example.

“Yesterday” by The Beatles

I hope, you succeed and felt all the nuances of the compositions :).