Discussion 2e - The Overtone Series

Class Discussion

“Why can we differentiate sounds?”

  • When early humans developed, it was important to be able to differenciate high and low sounds to hear the difference between predators and prey.

“Why are certain intervals consanant verses dissonant?”

  • When the frequency of a tone lines up well with the frequency of another tone, we hear it as consonant.

  • The most simple ratio we can create is 2:1, where a tone vibrates at one half the frequency of another tone. We call this an octave. The next simplest ratio is 3:2. We call this a perfect fifth. As the ratios between two frequencies become more complex, the interval becomes more dissonant.

“How do we differenciate timbre?”

  • Every sound produces overtones. We often hear just the fundamental, or the loudest tone or sound. Your brain organizes all of the extra tones in the overtone series into a bundle of sound we call timbre.

Overtone Series

  • Notes in the overtone series in C - C, C, G, C, E, G, Bb, C, D, E, F#, G

  • The order of the overtone series in intervals - P8, P5, P4, M3, m3, m3, M2, M2, M2, M2, m2

  • Major scales are based on stacking perfect fifths (the first interval with two different pitches)

  • Intonation is based on how you divide the octave. If you divide it into 12 equal tones (equal temperament), it doesn’t perfectly line up the the overtone series. The tuning system that uses the overtone series is calles “Just Intonation”.

Class discussion 2021

Two different systems for labeling the overtone series, either one is good

  • Fundamental + x overtone. Ex: in C, the Bb in the treble clef staff is the sixth overtone.
  • Partials, which do not differentiate between the fundamental and the other overtones. Ex: in C, the Bb in the treble clef staff is the seventh partial.

Methods for memorizing how to write out an overtone series

  • 854-3332 + Lydian scale to the fifth
    • This method requires you to remember the quality of the intervals in the “phone number,” and also that the “scale” includes the last note of the phone number as do
  • Can think of it as tonic, subdominant, dominant
    • Working in C, the first 4 notes suggest C, the next 4 suggest the dominant of F (C’s subdominant), and the last 4 are sol la ti do in G (C’s dominant)

Timbre = how your brain interprets the overtone series (Why someone’s voice is different than anothers. Why a piano sounds like a piano and a trumpet sounds like a trumpet)

A “big” sound (the kind we usually hear in professional musicians) just means that there’s a strong fundamental and a LOT of overtones in that person’s sound.

If the overtone series exists everywhere, how did different systems of music evolve?

  • In the case of gamelan and some types of Indian music, these systems were based off of the instruments constructed to play that music, not the voice

Major Sclae Makeup -All major scales are made up of all perfect fifths with one diminished fifth.

Equal Temperment vs Just Temperment -Equal temperment means that every note is eaqually separated -Just temperment is when each note is slightly further apart or closer together based on the key. In ensembles, you might have heard your director saying the third needs to be flat, or the fifth needs to be flat.