This professor bounces sound waves carrying music that can not be heard out loud but can be heard inside your head

This professor bounces sound waves carrying music that can not be heard out loud but can be heard inside your head.

This experiment was carried out at a college and I believe he played a Eagle's song.

Look at the student's reactions.

If a college professor can do this with a few hundred dollars, don't tell me our government isn't capable of activating mentally broken people to carry out heinous acts