The original Washington Post article which includes a short video clip of Bell playing can be found at http://www.washingtonpost.com/wp-dyn/content/article/2007/04/04/AR2007040401721.html
YouTube has a longer video at http://www.youtube.com/watch?v=hnOPu0_YWhw
Go to the Deems Weblog to read an article on the experiment. ( http://deems.wordpress.com/2009/09/29/perception/)
As a quick demo on perception, you might play just the audio portion of the subway video to your classes. Then play the audio of Bell playing in concert (http://www.youtube.com/watch?v=pp-Gl-70dSo. Lastly, show both clips and start what should be a good discussion on perception.
A special thanks to Adina Shmidman PhD, AP Psychology teacher in Bala Cynywd, PA for bringing this experiment to our attention.