10. The Overtone Series and Dissonance

If you like this Tutorial on Acoustics, please subscribe:    / walkthatbass  

For more information check out my website: https://www.thejazzpianosite.com/how-...

Have you ever wondered why we call certain intervals ‘perfect’? What’s so perfect about them? Well, the answer lies in the Overtone Series. The Major triad and the V-I Perfect Cadence were not randomly chosen, they are both derived from the Overtone Series.

While each instrument is different, generally, overtones get progressively weaker the higher up you go. So the 85th overtone is much harder to hear than the 2nd or 3rd overtone. So a rule we have to remember is that: Lower overtones are louder and harmonically stronger.

Each of these harmonics is a particular musical note. And, of course, any two notes, including harmonics, form some kind of interval. So every interval can be expressed as a ratio between the frequencies of two notes or harmonics.

So by playing a single note, you’re actually, in effect, playing the entire Major triad of that note. So as you can see, the Overtone Series is very important to music. It determines how music is structured. The Major triad and the V-I Perfect Cadence are not just things that were created out of thin air. They are inherent in the very structure of nature – music is a reflection of the laws of nature.