Every note has Overtones

Every note created by a string (as discussed in the last music theory lesson) not only has the note you hear, it also has harmonic overtones.


This means that, should you have three strings playing:

  1. First string play the root
  2. Second string 5/4 in length, playing the 3rd
  3. A third string at 2/3 in length, playing a 5th

Then these notes share the same overtones and when played at the same time, a most pleasant harmonic sound appear: a major triad.

The Major and Minor clash

Should you change the third to a minor third, or 6/5 rather than 5/4 in length you would get a minor chord, however, the major 3rd is still present in the overtones of the Root.

This means that you get a clash between the natural overtone of the Root (a major third) and the minor third.

This clash makes us experience the interval as “sad”, whereas when the 3rd was major, and it’s overtones perfectly repeated, we heard a “happy sound”.

The 3rd is as common in major and minor through out the chords we form when harmonizing a scale (more on this later).

Using the formula of repeating the natural overtones and then building new triads off those notes, we wouldn’t actually form a major scale, instead we have these notes created from that first major chord, and from now on I’m gonna use the note C a my starting point:

C Major Triad: C – E – G
E Major triad: E – G# – B
G Major Triad: G – B – D

Add them all up and we get this peculiar scale:

C D E ? G G#/Ab B

So there is no 4th and the A is flattened if we compare it with the standard major scale:


Two debates grew out of this:

Should the missing F be F or F#?
There’s a tone and a half gap between Ab and B, all other intervals are either a tone or a semitone away from each other.

So in ancient Greek times they simply raised the Ab to an A and decided to use an F#.

This gave us this basic scale:

C D E F# G A B, what we today call Lydian, a major scale with a #4.

Lydian as home

Lydian, to the Greeks was like major (Ionian) is to us today, it was seen as the home scale from which everything else was built.

This actually made complete sense since if you build all modes from this, the Lydian scale would feel the brightest, being the only scale with a # interval in relation to Root.

Putting Lydian first, we could describe the modes as going from sounding bright to sounding dark:

  • Lydian, one sharp, the #4
  • Ionian, no sharps or flats
  • Mixolydian, one flat, the b7
  • Dorian, two flats, b7 and m3
  • Aeolian, three flats, b7, m3, b6
  • Phrygian, four flats, b7, m3, b6, b2
  • Locrian, five flats, b7, m3, b6, b2, b5

However, after a few more thousand years of debate, a switch was made and music composed in Ionian as our home was what we all accepted as sounding most natural, at least in the west!

Sheet music has since this change been based around the underlying rule of the major scale in C major being our home.

For the modern guitar player this evolution of scales and sheet music means:

Without understanding that it is the Ionian mode that sheet music is built around it would be impossible to read and write music on the stave.

Without being able to play the Ionian mode in all positions on the guitar neck it would be impossible to read music.

The eBook Music Theory is now available.

-Dan (your guitar guru)

Guitar Conspiracy

About Guru

I have made up my mind: You Can Learn Guitar!

13 thoughts on “Overtones

  1. Pingback: How many notes in an octave? | Music Theory | Spy Tunes

  2. Nal

    Yeah, in between all this, philosophers like Aristotle had influential ideas about which modes people should listen or be taught as music was thought to influence the character of a person.

    So nothing to rough and nothing to sad. But then other philiosophers had different views.

    Still, after a lot of this Greek tradition was lost, it was ressurdcted by the church who transferred some of these ideas incompletely.

    The church being influencial kind both progressed and hijacked music simultaneously. Under the church music notation started to be developed, but they insisted on the use of certain modes (based on the ideas of Pythagoras, Aristotle etc).

    But the church didn’t own music and music was happening in the world around, it just was written down until the learned aristocracy showed an interest and which did a lot for bringing the music back to the people.

    Correct me if I’m wrong! :)

        1. Guru Post author

          Yeah I know, I have the same problem, on the phone it’s even worse cause it’s so small.

          When I write on the iPad I get many more spellings wrong, as well as it changes words sometimes.

          The only positive thing I’ve gotten out of that is that it made me read my text twice as a habit rather than hitting Submit. Saying that, from often becomes form and similar.

          It’s annoying…

  3. Guru Post author


    This is a very important point, the church really did go away from the modes and kind of said: Only major and minor is what we use!

    For example, the tritone was called the devils interval and banned!

    The tritone is the #4 so they really did go against the Greek who were much more advanced modally.

    1. Nal

      And they really liked their consonant intervals, it firs it was the fith and hen it was the fourth, or was it the other way around.

      The church was around for ages, and yes slowly evolved too. :)

      1. Guru Post author

        Yeah, from that initial interval discovery to writing music on the stave there are thousands of years!

        Just finding the major scale took forever.

        When I see a 7 year old play piano really well from sheet music I always think of that, the amount of time that went into developing all this is absolutely immense.

    2. Nal

      Oh yeah, and that’s why I say incomplete, because they did change things. It’s also like what you said once I think, once u allow one change like a dissonant interval, it opens the flood gates for all sort of other ‘acceptable’ changes, and the evolution continues.

      Another example, because of the churches’ trinity doctrine, for a long time, their music implied triple meter, that later changed too of course.

  4. Pingback: The Major Scale | Spy Tunes

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