Ann: Digital Speaker Development Update, page-27

the second video is not a sound based invention.

Sound does not carry much energy in its vibration. In fact there is a common physics problem whereby you yell at your morning coffee and all the of the energy is imparted directly into heat (by bassing the normal wasted energy in movement) and it still takes something like 8000 hours of yelling to boil one cup...

I'd expect as the guy did in the video, that it is an electrical force being imparted, such that if you measured ampage it would go through the roof as soon as it hit the water.