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toddalin
02-15-2007, 09:32 AM
Last night on Myth Busters, they were exploring the possibility of blowing a car apart from the inside using pure volume.

They fabricared a 56" woofer out of metal plate and used an inner tube as a surround. Diaphram was driven off of a Mercedes diesel drive shaft cut and reconfigured like a crank shaft. The "piston rod" is what actually drives the diaphram. No volumes control (full stroke with every revolution, and frequency was determined by engine speed. Speaker did ~165 dB at ~16 Hz before it blew the sunroof out of the frame and the speaker self destructed.

JBL was there to oversee the project with their BIG VAN system that uses many, many W15GTIs and thousands of watts to get interior volumes over 165 dB in the driver's position. The levels in the passenger position are so loud, JBL will not let anyone sit in there during demo for fear of disarranging their internal organs. :applaud:

Well you guys know my view on using W15GTIs in the home. :thmbsup: :moon:

http://www.largescaleonline.com/eimages/lsolpics/Team_Member_Pics/toddalin/center-2235-w15gti.jpg
:moon:

Tom Brennan
02-15-2007, 10:13 AM
"Diaphram was driven off of a Mercedes diesel drive shaft"

Sounds like something Tom Danley would do.

jim campbell
02-15-2007, 10:58 AM
i wish a few more of the rolling boom boxes and their fart can mufflers would self destruct.

4313B
02-15-2007, 12:13 PM
Well you guys know my view on using W15GTIs in the home. :thmbsup: :moon:
Yeah... you like higher Q drivers as opposed to lower Q drivers. That's your personal preference. Feel free.

I'm not real sure what the :moon: emoticons in your post are supposed to mean.

Mike Caldwell
02-16-2007, 08:06 AM
Hello
That was actually a rerun show from a few months back, but I watched again!
I think there speaker would have lasted longer if they had made up something to form a spider to hold their voice coil / crank shaft centered. You could see it yanking from side to side.
A few of their shows has featured speakers by Meyer Sound one show had John Meyer himself in it.

Mike Caldwell

boputnam
02-16-2007, 08:49 AM
I think there speaker would have lasted longer if they had made up something to form a spider to hold their voice coil / crank shaft centered. You could see it yanking from side to side.
Yea, I agree Mike. The excursion was terribly destructive. The surround was crap, too. FWIW, I thought the experiment was meaningless - whatever it was they built was not a proper cone transducer (even with it's mechanical motor).

duaneage
02-17-2007, 09:14 PM
With all the trouble they went through to make that silly speaker driven off the engine they could have used a pair of these:
http://www.mtx.com/caraudio/products/subwoofers/jackHammer.cfm
and gotten some real results. These speakers are sick.

Titanium Dome
02-18-2007, 07:23 AM
With all the trouble they went through to make that silly speaker driven off the engine they could have used a pair of these:
http://www.mtx.com/caraudio/products/subwoofers/jackHammer.cfm
and gotten some real results. These speakers are sick.

Check out this video. As the man says, this thing is "f#$$#n' ridiculous."

http://www.nearlygood.com/video/mtxjackhammer.html

Mike Caldwell
02-18-2007, 11:37 AM
What they built was close but not quite getting it! As I said in the other post they need a spider of sorts to keep the crank centered, maybe a fixed tube with the voice coil/crank sliding inside of it kind of like a piston. As for the surround I don't think they allowed enough for the excursion/crank throw. I'll look on the shows message board and see what if any other comments there were on it.

Mike Caldwell

louped garouv
02-20-2007, 11:02 AM
mythbusters screws up the tests all the time...

the "falling bullets" show comes to mind....

I think they often technically screw up the premise they are supposed to be testing....

they ended up giving the falling bullets show all three ratings....

basementbob
03-10-2007, 01:05 PM
Check out this video. As the man says, this thing is "f#$$#n' ridiculous."

http://www.nearlygood.com/video/mtxjackhammer.html


dont go to this site it is loaded with worms and virus.

Titanium Dome
03-10-2007, 04:06 PM
Really?

I didn't have any problems.

But


then


I'm


using


a


Mac. :dont-know

toddalin
03-10-2007, 05:36 PM
dont go to this site it is loaded with worms and virus.

Yes, and Trojans too! :biting:

hjames
03-10-2007, 08:18 PM
Yeah - if you didn't say it I'd be forced to ...

Gimme that Trojan site - he he he

The Power of OS X compells you!


(or something equally silly)


Really?

I didn't have any problems.

But


then


I'm


using


a


Mac. :dont-know

Zilch
03-10-2007, 09:23 PM
Only because you are unworthy of attack.... :p

Titanium Dome
03-10-2007, 09:46 PM
Only because you are unworthy of attack.... :p

The moaning of dinosaurs while the little mammals consumed their eggs. :biting:

Hoerninger
03-11-2007, 04:03 AM
(or something equally silly)

Yes, :DS/2 (IBM).

It runs and runs and runs
like a VW.
_____________
Peter

SEAWOLF97
03-11-2007, 03:32 PM
Really?

I didn't have any problems.

But


then


I'm


using


a


Mac. :dont-know

My little Apple Nano is superior hardware , but Apple iTunes for PC really sux. I hope their OS is better than the apps. I set in prefs and it cant seem to store them , back to defaults everytime it starts up. This is the only sw that has this issue on my PC.

toddalin
03-11-2007, 07:42 PM
Yeah - if you didn't say it I'd be forced to ...

Gimme that Trojan site - he he he

The Power of OS X compells you!


(or something equally silly)

Maybe, but maybe not.

Did you ever stop to think that maybe there really aren't viruses and trojans at that site, but there is a piece of code at the site that the PC is smart enough to recognize as a potential problem, when it really isn't :hmm: , or

Maybe you guys did pick these up, but your system is not reporting them to you, and eventually, they may manifest themselves as shingles under your armpits??? :p

hjames
03-12-2007, 04:15 AM
That is wrong in so many ways ...

First off, MS Windows is like a young kid that wants to show off to everyone it meets, inviting them in to share knowledge and wants to play with everyone. Its very design has open hooks to more easily interface with other programs and utilities, which, unfortunately, wind up being backdoor access for hostiles.

OS X is more cautious and generally requires some kind of sign-in, password, authentication by the sysadmin (user) before letting strangers get very far in.

There are exceptions, but its a whole different kind of trust arrangement.

Or maybe its just about the colours, man, lots of colours ...:applaud:




Maybe, but maybe not.

Did you ever stop to think that maybe there really aren't viruses and trojans at that site, but there is a piece of code at the site that the PC is smart enough to recognize as a potential problem, when it really isn't :hmm: , or

Maybe you guys did pick these up, but your system is not reporting them to you, and eventually, they may manifest themselves as shingles under your armpits??? :p