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The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

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Re: The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

#32
post #6

Bold title for WWDC day.

The mods have changed the title, so your comment makes less sense now. For those who are confused, the original title was something like "This is the best video you'll ever see!" or similar.

Re: The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

#34
post #31

Why is it sometimes asymmetrical vertically? Is it just a slight variation where the plate isn't perfectly square or the bolt not in the exact center?

It appears to be simply a lack of sufficient sand to show all of the lines- some of them become symmetrical when more sand is sprinkled on.

Re: The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

#37
post #33

Interesting, but for a similar experiment that's rather higher on the "cool" spectrum, check some of the videos with "oobleck" (non-newtonian fluid, like cornstarch and water) on an amp.

Here's the first one I saw, a couple of years ago:

http://www.youtube.com/watch?v=Yp1wUodQgqQ

Linking it here because I just went searching for new examples, and none of what I found was quite as good at fooling my brain that living creatures were crawling out of the muck...

Re: The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

#39
post #20

Earlier quoted context omitted.

I'm a cs person and never encountered this in school. Is this taught in engineering? Typical course names?

As a math person, I look at this and think "Fourier series". I encountered the ideas in both Classical Mechanics 1 (third year physics course where I took it) and Differential Equations (third year math course where I took it). It is still a nice visualization.

It's very close to Fourier series, but since the "solutions" (the equilibria) are not integer multiples of a fundamental, but solutions to a 3-dimensional wave equation, it's more like "wave equation."

Re: The Visual Patterns of Audio Frequencies Seen through Vibrating Sand

#40
post #39
post #20

Earlier quoted context omitted.

As a math person, I look at this and think "Fourier series". I encountered the ideas in both Classical Mechanics 1 (third year physics course where I took it) and Differential Equations (third year math course where I took it). It is still a nice visualization.

It's very close to Fourier series, but since the "solutions" (the equilibria) are not integer multiples of a fundamental, but solutions to a 3-dimensional wave equation, it's more like "wave equation."

From a mathematician's point of view it is a Fourier series. You have the property that any starting state can be divided into the sum of orthogonal components. No matter how complex the components are, that's still a Fourier series.

A physicist would disagree, I am sure. But to a mathematician, an orthonormal wavelet basis is also a Fourier series.

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