According to Wikipedia, "The Atari Video Music (Model C240) is the earliest commercial electronic music visualizer released." It takes music as input and "draws" a video signal that visualizes this input much like the visualization plugin of Winamp or Windows Media Player. Only that the Atari Video Music was created in 1976.
For configuring the visualization, there are six different parameters (top left to bottom right):
It also features an automatic mode which can be also configured using on of the "Shape"-switches. This mode only changes the parameters that are configured using the buttons, but not the dials. The "Horizontal" and "Vertical Display" button groups get different functions in auto-mode.
The larger the gain, the bigger your objects. For "Hole" and "Ring" the left audio channel drives the inside of the objects, the right audio channels always drives the outside.
The input signal also changes the color of the object displayed. The color is run by a palette which starting point can be configured using the "Color" dial.
At maximum you get clean, almost mathematical shapes. Turn these dials to the left and the shapes are not so well-structured anymore. Also here left and right behave similar to "Gain".
Here are three modes available:
Defines how many objects are drawn in one line: 1, 2, 3, or 5.
Defines how many lines of objects are drawn: 1, 2, 4, or 8.
This is probably the hardest question. There is no PAL version of the Atari Video Music, so I got mine from ebay.com (USA) for a pretty fair price being in an unknown condition. Right now (April 2017), working units are sold for over $400 there.
I originally wanted to repair mine myself at the local hackerspace, but I was lacking the time to do it. Talking about that with Dr. Stefan Höltgen of Humbold University Berlin, he made an interesting proposal: one of his students will repair it, and the institute gets it as a loan for one year. A nice deal for both sides. So it was fixed by Shockwav3 around the same time Ben Heckendorn did his fix of that machine.
"Atari Video Music - The Demo" is the idea to get something more structural out of this hardware. Videos you find on YouTube are shot in random mode. That's not what I wanted. First of all I needed music composed for the machine, a job made for Skyrunner. I showed him the machine and what it was capable of. For the track itself I had a few ideas: it had to be danceable, and the words "Atari Video Music" needed to be in it. Also the classical Atari commercial jingle would be a nice addition. Soon after that I also came up with the idea of having vocals done by a child. This place was taken by Hanna, the niece of Miss Ctrl who organized a fifteen minutes recording of her trying to get it said correctly. We ended up using the not so perfect parts from that session.
Once all the basic parts seemed to fit, we met to record the introduction.
After the final mix was set, it was up to me to come up with a "choreography". I listened to every part in a loop, deciding what pattern I want to put in that specific spot. There were also some patterns that needed to be in there, and for these I needed to find a sweet spot as well. The "mesh" at the end falls into that category. The result of this was a script called "The Code" typed into libreoffice calc. That was the easy part.
The hard part was getting that script done correctly in realtime. That was like trying to record a perfect run of Guitar Hero, Dance Dance Revolution, Wii Dance or something like that... but even the recorded run wasn't perfect to me, it was well enough to try the post-production steps like getting it into Movie Maker. There some more problems showed up, so after I had a first video up and running, I decided to call it a day. It also shows that it was done "live on tape" in one run.
P.S.: Thanks to all the people, who voted this little fun project to second place on Revision 2017. I'd never expected this.