I think it's computer generated but the following is how they described it......

"Turn your sound on for this. This is really cool. Read this first, then watch. This is almost unbelievable. See how all of the balls wind up in catcher cones. This incredible machine was built as a collaborative effort between the Robert M. Trammell Music Conservatory and the Sharon Wick School of Engineering at the University of Iowa . Amazingly, 97% of the machines' Components came from John Deere Industries and Irrigation Equipment of Bancroft , Iowa , yes farm equipment!
It took the team a combined 13,029 hours of set-up, alignment, calibration, and tuning before filming this video but as you can see it was WELL worth the effort. It is now on display in the Matthew Gerhard Alumni Hall at the University and is already slated to be donated to the Smithsonian."
http://www.youtube.com/watch?v=Impn_Yh8Zxo

It's very time consuming animation. Very Good, though.

R.

it is CG

Definitely CG - as a matter of fact, I have the video it's from..."Animusic, vol. 1" - very cool graphics actually generated via MIDI files. On the video is extra footage that explains the complexity of the project and how they accomplished it. It wasn't made from parts of a John Deer. It was the result of pure technological genius.
http://www.animusic.com/

Tim

thanks for the link, that was really nice... I was sure it was CD graphics and your link proved it!!!
Take Care

They used a John Deere computer to generate the graphics...

This one ain't fake ! http://uk.youtube.com/watch?v=HiXSe3GcP-8&feature=related
These boyze are JAMMMMMIN' !