Question about breaking a glass with sound waves

A MAKE reader named James wrote to us with a physics question. It’s in reference to the video above:

First of all, I wanted to say that you guys have the BEST vids on youTube!

I have started to read quite a bit about frequencies and I want to do this experiment.

If you watch the video, he breaks a glass using a signal generator and an oscilloscope.

The question I have is where you get the mic that hooks up to the oscilloscope and what is that bronze colored cylinder on right of the attached pic?

Obviously it emits and focuses the waves from the signal generator at the glass, but I cannot see this thing for sale online. Probably because I don’t know what it’s name is.

If you could help point me in the right direction so I can get the equipment and do the experiment, I would be very happy!

If you can help James, please post it in the comments section!

Mark Frauenfelder is the founding Editor-in-Chief of Make: magazine, and the founder of the popular Boing Boing blog.

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