Partial Intonation
Now that we have gone over how to build the Overtone Series, it is time to talk about one of the most useful aspects of the series: intonation.
While some partials are played in tune (Fundamental, 2nd, 4th, 8th, 9th,) others play out of tune to differing degrees. In the following diagrams we will point out the pitch tendencies of the Overtone Series.
While some partials are played in tune (Fundamental, 2nd, 4th, 8th, 9th,) others play out of tune to differing degrees. In the following diagrams we will point out the pitch tendencies of the Overtone Series.
The Octave Partials (2nd, 4th, and 8th)
All of the partials from the Overtone Series that produce and Octave of the Fundamental, are in tune. It is also good to recognize that the Octave Partials are doubled to the next Octave Partial. (1st Partial is the Fundamental, the 2nd Partial (1 x 2 = 2) is double the 1st, the 4th Partial is double the 2nd, and the 8th is double the 4th.
It is also helpful to remember how many octaves above the fundamental these Partials are: 2nd Partial = 1 Octave above Fundamental, 4th Partial = 2 Octaves above the Fundamental, and the 8th Partial is 3 Octaves above the Fundamental.
It is also helpful to remember how many octaves above the fundamental these Partials are: 2nd Partial = 1 Octave above Fundamental, 4th Partial = 2 Octaves above the Fundamental, and the 8th Partial is 3 Octaves above the Fundamental.
The 3rd, 6th and 12th Partials are Sharp
The 3rd, 6th and 12 Partials are all F's in this Overtone Series, and they are all sharp-played partials. This is why on trombone, tuba, and Euphonium open F's tend to be sharp.
Any note played on the 3rd, 6th, and 12th Partial of the Overtone Series will tend to be sharp.
Also notice the doubling pattern here as well: 12 is double 6, which is double 3.
Any note played on the 3rd, 6th, and 12th Partial of the Overtone Series will tend to be sharp.
Also notice the doubling pattern here as well: 12 is double 6, which is double 3.
The 5th and 10th Partials are Slightly Flat
The 5th Partial, which is a Major 3rd above the 4th Partial, and the 10th partial, which is a Major 3rd above the 8th Partial, are both slightly flat partials. Any note played on the 5th or 10th Partial will tend to be slightly flat.
Notice that the pattern continues in these related partials: 10 is double 5.
Notice that the pattern continues in these related partials: 10 is double 5.
The 7th Partial (It's Very Flat)
The 7th Partial is a minor 7th above the 4th Partial and is very flat.
If we were to look at the 14th Partial we would see that it would also be an Ab (but it would be a minor 7th above the 8th Partial) in this Overtone Series, and it would be flat as well.
If we were to look at the 14th Partial we would see that it would also be an Ab (but it would be a minor 7th above the 8th Partial) in this Overtone Series, and it would be flat as well.
The 9th Partial is in tune!
It's in tune!
The 11th Partial is flat
The 11th Partial is flat.
Alright, What's Next?
Now that you know what the pitch tendencies are for the overtone series, it's time to apply them to your instrument. Head over to the next page by clicking on "How Does It Affect Me?" in the "More..." section above.