Now this has gotta interest pickup makers

[JGundry]

Ok...? So what else is going on?

There are standing wave harmonics to the fundamental note. If you play a bass under a 60 cycle light source you will see a hint of these. If you play up and down the board you can see beats in some hot spots the length of the neck. The beats are where the nodal points of the standing wave harmonic are starting to synchronize with a multiple of the 60 cycle light source. There will be more or fewer nodal points depending upon which harmonic standing wave you are seeing.

[defaced]

I understand wave motion. I know what we're discussing is a standing wave, and I know that there can be harmonics - they are not a guaranteed in all transverse wave fixed end string vibrations - as I previously implied, it depends on where you pluck the string. Ok, so, now that we've got that out of the way, back to my question: what else is going on?

[frankfalbo]

Jon all snark aside I honestly thought you'd have an aha moment by now and we could be light hearted about it. Part of the reason I used humor was to create a soft landing. If you really think these videos are more accurately depicting string motion using strobe or rolling light source or image capture then we need to agree to disagree, and I apologize if the sarcasm was a detractor in the pursuit of absolute truth. For me, absolute comes in the form of high speed video (not rolling shutter) in sunlight or incandescent viewed in super slow-mo, like on Mythbusters. I see the shape of the string in your picture, it's nowhere near the radical multi-directional look of the videos we're discussing. I never implied a string only moves in a football pattern, but was explicit that these videos are what they are due to artifacts, not some breakthrough in string vibration analysis.

[defaced]

This is fun (this page autoloads an applet, FYI): Loaded String Simulation

"pluck" the string and let it run through a hundred cycles (turn up the simulation speed) and see that as with most things in physics, string motion is a complicated garbled mess. And looks nothing like the original video in this thread.

[JGundry]

Jon all snark aside I honestly thought you'd have an aha moment by now and we could be light hearted about it. Part of the reason I used humor was to create a soft landing. If you really think these videos are more accurately depicting string motion using strobe or rolling light source or image capture then we need to agree to disagree, and I apologize if the sarcasm was a detractor in the pursuit of absolute truth. For me, absolute comes in the form of high speed video (not rolling shutter) in sunlight or incandescent viewed in super slow-mo, like on Mythbusters. I see the shape of the string in your picture, it's nowhere near the radical multi-directional look of the videos we're discussing. I never implied a string only moves in a football pattern, but was explicit that these videos are what they are due to artifacts, not some breakthrough in string vibration analysis.

No problem Frank. I figured you where intending it to be a lighthearted critique. Good to know it was.

The string simulator defaced posted is cool. What I think it really shows is the string vibration we see in slow motion images is a combination of the fundamental and all of the harmonics working on the string at once. That is why that string simulation looks like a mess when you switch from the fundamental. Since there is just one string all of this motion is a jumble when viewed all together. But the entire motion is really a combination of wave phases that can be visually isolated by strobe, CRT, or video. I do think some artifacts are added by the video but at the core is movement that is a direct function of the harmonic phase of the string's movement.

For all I know this is what you were getting at Frank.

[belwar]

... in the form of high speed video (not rolling shutter) in sunlight or incandescent viewed in super slow-mo, like on Mythbusters.

^ this would be the correct way to see what was going on IMO. Somewhere between 1000 and 5000 frames per second you would get a really good idea what was going on.

[Joe Gwinn]

That camera takes 5,000 frames per second, while the fundamentals of most of the strings are below a few hundred Hertz, so we should be able to see at least the lower ten harmonics in the videos, and more in the longer strings.

I would believe that camera (built for just such uses) over cameras intended for snapshots and home videos.

The distortion effect has been well known since the advent of focal plane shutters, introduced in the 1930s by Leica, the inventor of the 35mm film camera. In most 35mm cameras, the shutter curtain moved upwards or downwards, causing things moving horizontally to be tilted diagonally. Things moving vertically were lengthened or shortened in the vertical direction.

Focal-plane shutter - Wikipedia

[RedHouse]

Oh c'mon guys, a little too serious aren't we? here, have a valentine cookie, it will take your mind off the minutia of spaghetti strings....



Now then, all better?

[Mark Hammer]

Gives "edible underwear" a new meaning, doesn't it?

D'ja ever see the episode of Saturday Night Live that Patrick "Captain Picard" Stewart hosted? They had a sketch where he operated an "erotic bakery". And while they did not show any of the presumed product, every customer entering the bakery would be revulsed by his "erotic" cakes, all of which revolved around women using the toilet, and all of which garnered a half-glazed/fully-crazed gleam and smile from Stewart, as baker, saying "Yes, erotic, aren't they?".

[David King]

No one here ever take a ship over to Europe and beat on the guy wires going up the mast? That's an endlessly fascinating way to spend a week if you're a 9-year-old who likes the wind in your face. Any suspended 1" steel cable over 50 feet long will do.

[David King]

Here's a hilarious, bare-assed video clip with naked dancing bears and kittens in a wineglass too..
YouTube - Plek Technology Strobe

[David Schwab]

I didn't watch any of the videos linked, except the Plek one. But back in the 70s a friend of mine had a lab quality strobe light. You could alter the rate and width of the strobe flashes. I used to look at the strings on my bass while changing the strobe rate to match, and it was really freaky. You would see the string doing this slow undulation like it was moving in slow motion, just like in the Plek video. Fretting a higher note would make the string move faster, just as you would expect.