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Kirbs17
10-02-2009, 02:44 PM
Title says it all

http://www.liveleak.com/view?i=6c3_1254185548
theken
10-03-2009, 10:30 AM
Can't watch video. But mythbusters did it
Thomas Gabriel
10-03-2009, 10:46 AM
Definitely possible. My dad did it in his home theater.
spike98
10-03-2009, 12:05 PM
Mythbusters also went one step further and had the dude do it with his voice. Not an amplified speaker.
theken
10-03-2009, 12:24 PM
Its all about the resonant frequency of the glass. And if you can match the pitch and make it vibrate enough the glass will shatter
kylejw
10-03-2009, 01:50 PM
Works with more than just glass too. Crankshafts, bridges...
inline6turbo
10-03-2009, 02:05 PM
Originally posted by kylejw
Works with more than just glass too. Crankshafts, bridges...

If you put the boom box next to your car your crankshaft will break?

...


I think mechanical vibrations are a smig different then what OP's talking about.
kylejw
10-03-2009, 02:18 PM
So the glass vibrating is not a 'mechanical vibration'?

Why do cars have harmonic dampeners?
inline6turbo
10-03-2009, 02:32 PM
Originally posted by kylejw
So the glass vibrating is not a 'mechanical vibration'?

Why do cars have harmonic dampeners?

They limit the amplitude of the torsional vibrations due to mainly the firing pulses and inertia loads transmitted to the crankshaft by the reciprocating assembly.

Smig different then singing at a glass and matching its resonant frequency without physically applying a force to it. Sound waves are much more interesting then physical force applied
kylejw
10-03-2009, 02:35 PM
And what happens when torsional vibration occurs at the resonant frequency of a crankshaft?

Personally I find this way more interesting:
http://www.youtube.com/watch?v=Ce-PQqkIXe0

But it's all resonant frequency anyways and that's all I meant. Whether it's sound, periodic explosions, wind or footsteps, I was just pointing out that this occurs in more than just glass.
inline6turbo
10-03-2009, 02:41 PM
Originally posted by kylejw
And what happens when torsional vibration occurs at the resonant frequency of a crankshaft?

Dude I totally understand what you're trying to say. They're just not sound generated.
FiveFreshFish
10-03-2009, 02:45 PM
Sound is a pressure wave. The medium is air.
clem24
10-04-2009, 11:23 PM
The slow mo is kind of cool.
broken_legs
10-05-2009, 07:49 AM
looks like quadropole sonic LWD
Mar
10-05-2009, 08:59 AM
The guy on Mythbusters broke crystal I believe, not glass. But one of my friends did crack his taillight with a subwoofer in his trunk.
mazdavirgin
10-05-2009, 10:16 AM
Originally posted by inline6turbo
If you put the boom box next to your car your crankshaft will break?

I think mechanical vibrations are a smig different then what OP's talking about.

A big enough boom box would move your car never mind break your crankshaft... Sound is a pressure wave in a medium. The medium happens to be air. You don't even have to match the resonating frequency of an object to destroy it or render it non functional. Think of it this way... A bomb blast is a moving front of air pressure which is in fact an extreme of a sound wave.
clem24
10-05-2009, 10:25 AM
Originally posted by Mar
But one of my friends did crack his taillight with a subwoofer in his trunk.

I wonder how many of these smrt kids these days will suffer permanent hearing loss by the time they reach their 30s or 40s. I especially cringe at all the kids on the LRT blasting music through their headphones. :facepalm:
Mar
10-05-2009, 12:55 PM
Originally posted by clem24


I wonder how many of these smrt kids these days will suffer permanent hearing loss by the time they reach their 30s or 40s. I especially cringe at all the kids on the LRT blasting music through their headphones. :facepalm:
Unfortunately I'm included. Whenever I blow my nose I have to plug my ear with my finger because the air squeezes out there. It's more from distorted sound though, rather than loud bass. If you're pushing proper clean sound you won't have much of a problem. Comes from cheap setups.