Why Does Music Only Use 12 Notes?

Why is it that there are only 12 notes used in music? Why not 13 or 14? It comes from the circle of fifths. Much of Western music is built on the relationship between the tonic and the dominant. If we are to work out the dominant of each dominant then we end up with 12 keys. These 12 keys can be arranged into the circle of fifths.

Many of you may already be familiar with the harmonic series, but in this lesson, I use the guitar to demonstrate how we can find these notes, and how they can be arranged to create the circle of fifths.

Many other cultures have more than 12 notes, and it is possible to find microtones in much of Western music. This video addresses why traditional Western harmony is based around the same 12 keys.