Imagine a beautiful melody (remember Ode to Joy from Beethoven’s 9th Symphony?).
Now imagine that your beautiful melody is like the outside of the best house you can imagine. How about a gingerbread house, just like Hansel and Gretel found in the forest? Your melody is all the delicious sweets on the roof, the chocolate icing dripping down the walls; all the shiniest and best bits which make that gingerbread cottage look wonderful.
But what would happen if you didn’t have the gingerbread walls? It’s no good having sweets on the roof if there is nothing to hold the roof up!
Our melody sounds lovely but needs something to hold it up, and that something is the vertical structure in music underneath our horizontal melody.
Listen again to just the melody of Ode to Joy, played in the video below by the cellos for about 30 seconds:
And now listen to the same theme with the rest of the orchestra providing the supportive harmony, again for about 30 seconds:
Suddenly, it sounds like a full musical structure. It sounds like a musical gingerbread house with walls, and a roof, as well as delicious melodic sweets and decoration.
So what is harmony? If melody is notes heard one after the other, harmony is notes heard at the same time.
The word ‘harmony’ comes from the Greek word ‘harmonia’ which means to be ‘in agreement’. The rule in classical music is therefore that harmony is when many notes sound together and, rather than arguing with each other and sounding bad together, they are in agreement and sound lovely.
Having said that, rules always seem to be there to be broken! Over history, composers have experimented with harmony and today, ‘harmony’ is as much about ‘dis-harmony’ (argument) within music as it is about ‘harmony’ (agreement). For now though, let’s look at when the notes are in agreement and sound harmonious.
Which notes go well together? In music, you get groups – or families – of notes that get along together particularly well. We call each of these families a ‘key’. Mozart’s Symphony No.40 is in the key of G minor, using notes from that G minor family that fit very well together.
Harmony is like thinking about music vertically, and when we stack notes one on top of the other that go well together you create something called a ‘chord’.
At the bottom of the chord is the bass (its other fancy names are the root or the tonic). This is the note which all the rest of the notes have to agree with and we’ll talk more about how important the bass is in this next section.
Meanwhile, you can read more about harmony and keys here.