Chords and Triads

Triads are made up of 3 notes played on top of each other. You will often hear people describe triads as chords. They consist of a bottom note (root), a middle note (3rd) and a top note (5th)

Music theory triad

How to make a triad

Triads are easy to create – all you need to know is your alphabet and how to count to 8!
First, work out which note you want to build your triad on (in our example we are building one on C).
Now start at the bottom note and count up 3 to get the next note (include the starting note when you’re counting) (in our example, 3 notes up from C is E).
Now start again at the bottom note and this time count up 5 (5 notes up from C is G). So, to build a triad on C we have used the notes C-E-G.

c major triad keyboard and sheet music

Easy, right?
Now, the tricky bit. You will find that if you build triads starting on different notes then they may sound very different. The type of triad depends on the number of semitones separating each of the notes. Let me explain…

Different Types of Triads

There are 4 different types of musical triad:

Happy and Sad Triads

Listen to the difference between a triad built on C (C-E-G) and one built on A (A-C-E). The first one sounds positive/happy (this is a major triad), whilst the 2nd one sound negative/sad (this is a minor triad).

      Major and Minor Triad audio clip

So why the difference?

The difference in sound is due to the change in number of semitones between the root and 3rd notes. Look at the keyboards below:

c major and a minor triad keyboard

Can you see that the difference between the bottom (root) and top (5th) notes stays the same (there are 7 semitones between the bottom and top notes in both triads – rather confusingly we don’t include the starting note when counting up semitones!).

The difference is in the interval between the bottom (root) and middle (3rd) notes.
In the major triad there are 4 semitones between C and E – 4 semitones equals a major 3rd (hence the happy sound in a C major triad).
In the minor triad there are only 3 semitones between the A and C – 3 semitones equals a minor 3rd (hence the sad sound in a minor triad).
OK. So that’s not too complicated. What about the other 2 types of triad?

Scary and Mysterious Triads

There are 2 other types of triad – both of which have a slightly unnerving sound quality.
The first is a diminished triad – this is a variation of a minor triad.
To create a diminished triad all you need to do is play a minor triad and then lower the top note by 1 semitone (there are now only 6 semitones between the bottom and top notes of the triad – this is called a diminished 5th). Have a look at the example below and listen to how scary and tense it is!

C diminished triad keyboard

      diminished triad audio clip

The other triad is called an augmented triad. To create an augmented triad, play a major triad and then raise the top note up by a semitone (there are now 8 semitones separating top note and bottom note – this is called an augmented 5th). This sounds even more unnerving and is rather mysterious.

C augmented triad keyboard

      augmented triad audio clip

Hope that all makes sense?

Next, we are going to have a look at Primary Chords.