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The World of Harmonics – With a Coffee, Guitar and Synth

78 points by gregsadetsky 6 days ago | 15 comments

elihu 13 hours ago

A minor terminology quibble: the video refers to the Nth harmonic as if it's the fundamental frequency times N+1, but it's usually fairly standard to refer to the frequency that's N times the fundamental as the Nth Harmonic. So, the fundamental is the 1st harmonic.

For overtones, there's less of an established standard, but usually the 1st overtone is twice the fundamental, the 2nd overtone is 3x, and so on. (I tend to avoid talking in terms of overtones because of the ambiguity.)

reactordev 12 hours ago

I think that makes it easier for those who are math brained and not creative brained. To understand music theory fully, you need that creative brain. Because we aren’t even talking about resonance harmonics, triplen, or any of the crazy interharmonics.

edit

actually watching again, at the very beginning, he demonstrated resonance harmonics.

Rochus 13 hours ago

> that's N times the fundamental as the Nth Harmonic

It's not actually "N times", isn't it?

elihu 11 hours ago

If the fundamental is 100hz, then the 1st harmonic is the fundamental (100hz), the 2nd harmonic is 200hz, the 3rd harmonic is 300hz, and so on.

Sometimes the harmonics aren't exact. On a piano, if the fundamental is 100hz then the 2nd harmonic might be, say, 200.1hz or something. Some inharmonic instruments like gongs aren't anywhere close to the "ideal" harmonic series.

TheOtherHobbes 9 hours ago

Membranes have a harmonic series in two axes - kind of. They have complex (not that kind of complex, although it also is, in a way) modes on a constrained surface which are calculated with Bessel functions.

In three dimensions you get atomic orbitals.

dsego 10 hours ago

Piano is even tuned with stretched tuning to match the harmonics better.

leephillips 9 hours ago

This may be overly pedantic (even more so than your correct comments about numbering harmonics and overtones), but in this case the overtones are not harmonics, which, as you say, are by definition multiples of the fundamental frequency (“harmonic series” is a mathematical term). That’s why gongs are “inharmonic”: they have an overtone series that is not a series of harmonics.

rhinoceraptor 5 hours ago

If you have an analog oscilloscope, it's really cool to put a guitar signal into it, you can play an open string and see all its harmonics, then play a harmonic and you just see the one harmonic.

nexus6 9 hours ago

Cool that’s the guy behind MyNoise. The background audio generator. Nature sounds, Synths, Ambient, ETC. Has mobile apps as well.

HelloUsername 5 hours ago

Youtube link: https://www.youtube.com/watch?v=DfbLBaDCsRU

hypertexthero 8 hours ago

My favorite part of the video is when Stéphane “makes a mistake” and shows it, like enlightened people, such as Cliff Stoll — https://www.youtube.com/watch?v=9yUZTTLpDtk — do :)

Elias-Braun 9 hours ago

the pømp in this coffee mashine isn't rotating

lonelygiraffe 13 hours ago

Cool video. Thanks! Going to make some coffee and play my guitar (-:

import 9 hours ago

That was a really good one.

sargx 9 hours ago

ohhhh i loved it!