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Comment by bweitzman | Hacker News Reader

Like the article (thankfully) mentions, the photographs really do have nothing to with the notes themselves. Intervals and chords have characters, individual notes do not.

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Indeed, this experiment says as much about the shape and size of the vessel that holds the liquid as it does about the notes. It's not true that you'd get the same result if you repeated it at home, unless your apparatus was built exactly the same.

Also, D minor is the saddest of all keys.

Spinal Tap?

https://vimeo.com/92699399

Of course :)

That was my thought as well, that the combination of note frequency and box size creates the standing waves photographed.

It's still beautiful to look at though....

Perhaps I missed that then because I found no mention of intervals and chords. They seem to explicitly say that they captured pure tones (220Hz for A). This sentence also made it sound as if they were generating a pure note (frequency), "As each note’s unique vibration induced its characteristic pattern into the water, Brown captured it with her camera." Then they went through the chromatic scale capturing each note.

I do wish they posted more about how they set this up. It sounds straight forward and if using pure tones should be easily reproduced...

It's the last paragraph of the article.

Yeah that article presents a poor understanding of cymatics.

However, you can think of the resonant body of the vessel that contains the water as one half of the interval. It's the relationship being the note and its environment that produces the unique pattern. If the vessel were to change, the image would too. It has nothing to do with the intrinsic value of the note alone.

The article is unfortunately a bit unclear, but it's not true that they have "nothing to do" with the notes. They are just a bit noisier than what we've perhaps seen before.

Would you say these pictures have "nothing to do" with the notes?

http://www.thisiscolossal.com/2013/06/the-visual-patterns-of...

Yes, it is a function of the note/frequency and the medium, not just the note, but that still means they are very much related tot he notes.

In particular you can see the different circular symmetries pretty clearly through the noise.

http://thekidshouldseethis.com/post/20902918854

Yeah I think those patterns are completely irrelevant when talking about the characteristics of notes and combinations of them.

Yeah I noticed that. But can someone explain how she got such varied patterns from individual notes?

I agree that the picture may say more about the vessel and the water than the note itself. But then why do the pictures look so different? Was there a different vessel per note?

When the tuner registered a note—reading 220 hertz, the frequency that produces an A, for instance—Louviere stopped adjusting. As each note’s unique vibration induced its characteristic pattern into the water, Brown captured it with her camera. The pair worked together to obtain a “portrait” of each of the 12 notes.

The sound waves induce a surface wave in the 2d plane of the surface of the water.

This surface wave reflected reflects of the side walls of the container.

At specific frequencies, the reflected waves will interfere with the generated waves in such a way as to cancel the amplitudes out completely at certain points, and double amplitudes at other points. When these points are stable, the pattern is known as a standing wave.

The standing waves are the patterns shown here. Imperfections in the container, the medium, and the way the sound source is transmitted to the medium make the patterns imperfect. If they were perfected, they would have a more symmetric, kalaidescopic appearance: https://www.google.com/search?q=kaleidoscope&source=lnms&tbm...

Intervals and chords have characters, individual notes do not

Yes they do, in the forms of texture and timbre.

Notes do not have timbre, they are just named pitches (which themselves are just frequencies).

Hm? If it's about how they appear on the staff, why make the distinction?

There are different ways to assign pitches to notes. What is commonly used in modern western music is called equal temperament, but there are other systems, like just intonation, for example.

The pitches in alternate tuning systems like JI and maqam are sometimes, but not always, denoted with extra information. Quarter-flats, cent indicators, and so on, distinguish the note-pitch representations. While tuning systems can indeed be transposed or converted to unmodified standard (ET) staff notation, that's more of a convenience that has its own learning curve.

So, in JI you wouldn't simply use 'A' to represent (e.g.) 440Hz, it might be A 4, for the "A" key (or "A" staff position) having a 4 cent difference than ET A.[1]

1. http://lilypondblog.org/wp-content/uploads/2015/11/example.p...

i thi in common usage 'note' could cover both your narrow meaning and his the parent comment's wider one.

Tell that to someone with perfect pitch.

Absolute pitch doesn't require you assign character to the notes that you remember. Well, I don't, so I count as a counterexample. I'm no synaesthetic that way, at least not in any conscious way.

I don't have it, but from what I've read it seems most people with absolute pitch associate some sort of character to pitches or at least keys. I'm sure that it's not a requirement.

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