In this classic column, Our Perfect Master replies to an irate reader,
On tonight’s episode of Mythbusters a leather-lunged vocalist whose name escapes me succesfully shattered a lead-crystal wine glass with his unamplified voice. He had to try 20 times and hold the glass directly in front of his mouth but he did it. Adam was able to accomplish an amplified glass shattering easily.
We’ve brought this to Cecil’s attention.
I recall seeing a soprano do this on British TV when I was a kid. Might have been a programme called Record Breakers. Not sure though, so not very helpful I guess…
I also have the impression - as Cecil explains - that it’s a question of producing the same frequency as the natural tone of the glass, not sheer loudness alone.
Also doubt many top class opera singers would wish to attempt such a novelty feat.
Oliver
That’s exactly the point about glass vs. crystal. Crystal has a much more specific resonant frequency than glass does. Try swirling a damp finger around the rim of a glass goblet and a crystal goblet and notice how easily the crystal produces a tone – the resonant frequency.
I’m confused, Mathochist. Are you saying that crystal (as in, a crystal goblet) is not glass?
I’m saying it’s a more specific term. All crystal stemware is made of glass, but not all glassware is crystal. As I understand it, crystal has a microscopic crystalline structure (unsurprisingly), but glass isn’t nearly so ordered. Crystal is much more susceptible to resonation than glass is, as evidenced by the experiment I mentioned. I wouldn’t expect a glass to shatter very easily any more than I would expect a bridge designed without a strong resonant frequency to shake itself to pieces like the Tacoma Narrows bridge.
I did not know that. It seems like it would have to cool a lot slower to make crystals.
I wasn’t able to find any concrete info on the web.
Well, even if I’m wrong about the microstructure, the experiment I mentioned shows that crystal easily hums a resonant frequency while glasses at best squeak with friction of fingertip against glass. If I had a video camera I’d demonstrate on my own Riedel tasting set and the cheapo glass stemware my parents bought for me in case I ever have dinner guests.
Yes, I saw the same episode of Mythbusters and recall them saying it was the first time this had been documented on camera.
For that matter, I’ve “sung” (run my finger around the rim) quite a few glass drinking vessels, some of them very cheap. I’ve never found one of the right shape I couldn’t do it with, and I’d be surprised if all of them were crystal.
Yes, you can get pretty much anything other than a beer mug to sing if you rub the rim enough, but glass uh… glasses will usually produce a fairly weak “eeek” and may take a few revolutions around the rim and varying the pressure before they sound. Crystal glasses will readily sing strong clear tones with just a light stroke.
Is this because they’re crystal, or because the makers of crystal stemware have better manufacturing techniques than those that make just plain glass stemware. ie: consistent thickness, symmetry, etc.
The next question is - is it necessarily the material itself, or does the shape play into this? I’ve got a large brass handbell of the “come in from recess” variety (as opposed to a pitch-specific musical handbell) and while it rings in the standard manner nicely, if I rub the edge of the bell with a smooth wood dowel, it will emit an amazingly loud continuous tone.
Question for Mythbusters: Will the echo of a duck’s quack, sufficiently amplified, be able to shatter a glass?
