5 ms·

So all overtones are harmonics. All harmonics except the fundamental are overtones? Edit: I never realized the fundamental was a harmonic. I thought all harmon

by hashkb 6y ago

So all overtones are harmonics. All harmonics except the fundamental are overtones? Edit: I never realized the fundamental was a harmonic. I thought all harmonics had to be above the fundamental. I thought the overtones were the multiples (e.g. higher octaves) and harmonics were other intervals produced by the instrument (organs being the most extreme example and maybe oboe being the least)

schoen 6y ago
Might be a terminological ambiguity -- like in mathematics you can distinguish "subsets", "proper subsets", and "nontrivial" (or "nonempty") subsets. Or "divisors" and "nontrivial divisors" and "proper divisors". Even though the terminology can be defined in order to make these distinctions clear, there's an arbitrariness in terms of which definition you prefer (in the past, some mathematicians treated 1 as prime, which makes the definition of a prime simpler, but makes many theorems about primes more complicated to express). And there's a likelihood that even experts will sometimes use the simple term informally when they technically mean a more specific thing (like occasionally saying "divisors" instead of "proper divisors", or something). I imagine that acoustics experts have a definition available that definitively states whether the fundamental "is" a harmonic, but in certain contexts it intuitively makes sense either to include or exclude it, regardless of that. A similar case might be "animals"; taxonomically humans are animals (and apes), which is very important sometimes and confusing other times.
- hashkb 6y ago
  The fundamental being in or out of the set is less interesting to me than the (useful, to me in my day to day) distinction between overtones and harmonics. Technical misunderstandings really mess up rehearsals so I try to be as accurate as possible with the objective stuff so I can use it to communicate the subjective stuff.
enriquto 6y ago
> So all overtones are harmonics. Not at all! It's the other way round. Harmonics are those overtones that are integer multiples of the fundamental. You can have other, non-harmonic, overtones.
- hashkb 6y ago
  Just to make sure I've got it: harmonics will always sound like (be?) octaves relative to the fundamental. But all the less-dominant frequencies are overtones, even if I somehow get a tritone or something gross sounding. Now what happens when I play a chord and get overtones out of the interaction between two strings or a choir? What's happening there?
  - enriquto 6y ago
    > Now what happens when I play a chord and get overtones out of the interaction between two strings or a choir? What's happening there? Nothing. Sound superposition is linear. There's no interference between different frequencies. By playing several strings together you obtain the sum of the sounds played by each of them separately. No new frequencies can appear.
    - ghusbands 6y ago
      Overly simplistic. You can get beats when you combined two nearby frequencies. The beats have a frequency and are audible. Similarly, sounds can be reinforced or hidden in the interaction between instruments; it might be linear, but that does not say anything about what you actually hear.
      - tripa 6y ago
        Overly confrontational. You can and do get beats when combining nearby frequencies, and it's not at odds with sound superposition being linear. The beats have a frequency and are audible, but their frequency is not a pitch.
  - djeiasbsbo 6y ago
    Yes, you got it. Important is that a wave has a frequency and also a shape (e.g. sine, square, etc.). Even if the shape is different and the frequency is the same, the "pitch" is the same. The shape is the "timbre", or what makes the instruments sound different. You can deconstruct any given sound wave into its partial sine waves. This is typically done using a Fourier Transform algorithm (FT). Of course, we can also do it the other way around, create a signal out of many sine waves. In practice, this is called additive synthesis. Instruments not only sound different because of the timbre. Another thing to look at is the loudness over time, e.g. when plucking a string. We usually do this with an ADSR representation (Attack, Decay, Sustain, Release). Knowing these chracteristics is enough to recreate an instrument with a synthesizer. Of course, it gets more complex when there are inharmonics and if they are irregular (different depending on each tone). That's why synthesizing instruments realistically is a pretty time consuming science.
SeanLuke 6y ago
The fundamental is harmonic #1. This is the case for essentially all additive synthesizers for example. Overtones are any partials other than the fundamental. While overtones CAN be non-harmonic (notably in bells), I think it's fair to say that most of them, or at least the most important ones, are usually harmonics. This is because the terms "fundamental" and "overtone" are historically music terms, and are generally applied to sounds we perceive as tonal or musical: and such sounds are largely composed of harmonics.

by hashkb 6y ago

schoen 6y ago

Might be a terminological ambiguity -- like in mathematics you can distinguish "subsets", "proper subsets", and "nontrivial" (or "nonempty") subsets. Or "divisors" and "nontrivial divisors" and "proper divisors". Even though the terminology can be defined in order to make these distinctions clear, there's an arbitrariness in terms of which definition you prefer (in the past, some mathematicians treated 1 as prime, which makes the definition of a prime simpler, but makes many theorems about primes more complicated to express). And there's a likelihood that even experts will sometimes use the simple term informally when they technically mean a more specific thing (like occasionally saying "divisors" instead of "proper divisors", or something). I imagine that acoustics experts have a definition available that definitively states whether the fundamental "is" a harmonic, but in certain contexts it intuitively makes sense either to include or exclude it, regardless of that. A similar case might be "animals"; taxonomically humans are animals (and apes), which is very important sometimes and confusing other times.

hashkb 6y ago
The fundamental being in or out of the set is less interesting to me than the (useful, to me in my day to day) distinction between overtones and harmonics. Technical misunderstandings really mess up rehearsals so I try to be as accurate as possible with the objective stuff so I can use it to communicate the subjective stuff.

enriquto 6y ago

> So all overtones are harmonics. Not at all! It's the other way round. Harmonics are those overtones that are integer multiples of the fundamental. You can have other, non-harmonic, overtones.

hashkb 6y ago
Just to make sure I've got it: harmonics will always sound like (be?) octaves relative to the fundamental. But all the less-dominant frequencies are overtones, even if I somehow get a tritone or something gross sounding. Now what happens when I play a chord and get overtones out of the interaction between two strings or a choir? What's happening there?
- enriquto 6y ago
  > Now what happens when I play a chord and get overtones out of the interaction between two strings or a choir? What's happening there? Nothing. Sound superposition is linear. There's no interference between different frequencies. By playing several strings together you obtain the sum of the sounds played by each of them separately. No new frequencies can appear.
  - ghusbands 6y ago
    Overly simplistic. You can get beats when you combined two nearby frequencies. The beats have a frequency and are audible. Similarly, sounds can be reinforced or hidden in the interaction between instruments; it might be linear, but that does not say anything about what you actually hear.
    - tripa 6y ago
      Overly confrontational. You can and do get beats when combining nearby frequencies, and it's not at odds with sound superposition being linear. The beats have a frequency and are audible, but their frequency is not a pitch.
- djeiasbsbo 6y ago
  Yes, you got it. Important is that a wave has a frequency and also a shape (e.g. sine, square, etc.). Even if the shape is different and the frequency is the same, the "pitch" is the same. The shape is the "timbre", or what makes the instruments sound different. You can deconstruct any given sound wave into its partial sine waves. This is typically done using a Fourier Transform algorithm (FT). Of course, we can also do it the other way around, create a signal out of many sine waves. In practice, this is called additive synthesis. Instruments not only sound different because of the timbre. Another thing to look at is the loudness over time, e.g. when plucking a string. We usually do this with an ADSR representation (Attack, Decay, Sustain, Release). Knowing these chracteristics is enough to recreate an instrument with a synthesizer. Of course, it gets more complex when there are inharmonics and if they are irregular (different depending on each tone). That's why synthesizing instruments realistically is a pretty time consuming science.

SeanLuke 6y ago

The fundamental is harmonic #1. This is the case for essentially all additive synthesizers for example. Overtones are any partials other than the fundamental. While overtones CAN be non-harmonic (notably in bells), I think it's fair to say that most of them, or at least the most important ones, are usually harmonics. This is because the terms "fundamental" and "overtone" are historically music terms, and are generally applied to sounds we perceive as tonal or musical: and such sounds are largely composed of harmonics.