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Old 09-27-2009, 10:12 PM
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Originally Posted by Mat-Romain
138.735 is the exact number that glass will break, anything more and its instant
Aren't the last digits Reoccuring? like 78450824356423975293475479837985423905278435789245 92743579825723457842503747428357235792748\
Like Pi?
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Old 09-27-2009, 11:17 PM
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the source sells this sound meter
Scosche Portable Sound Level dB Meter | Sound Meters | TheSource.ca is this something I could use to get a rough idea on spl.
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Old 09-28-2009, 07:14 AM
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Originally Posted by Ramon
the source sells this sound meter
Scosche Portable Sound Level dB Meter | Sound Meters | TheSource.ca is this something I could use to get a rough idea on spl.
i have that stupid thing. 129.9 is the loudest i can get on that stupid thing. i want my 29.99 back but i lost the bill. hahahhah
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Old 09-28-2009, 09:10 AM
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Originally Posted by Killer_klown187
Aren't the last digits Reoccuring? like 78450824356423975293475479837985423905278435789245 92743579825723457842503747428357235792748\
Like Pi?


absolutely, i just didn't want to get to technical
 
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Old 09-28-2009, 10:44 AM
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Originally Posted by Menace
i have that stupid thing. 129.9 is the loudest i can get on that stupid thing. i want my 29.99 back but i lost the bill. hahahhah

lol what the hey I got it today for 55 bux. I get the flash too when i put it in my trunk. It says like 129 too but I am not sure what to do with that number cause I dont think that is spl but just the level of sound. Anyone would like to help me out here on how to get a rough idea of the spl.

thanks
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Old 09-28-2009, 10:50 AM
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Originally Posted by Ramon
lol what the hey I got it today for 55 bux. I get the flash too when i put it in my trunk. It says like 129 too but I am not sure what to do with that number cause I dont think that is spl but just the level of sound. Anyone would like to help me out here on how to get a rough idea of the spl.

thanks
use the square derivative of the tangent function formula to figure out your spl with out a meter.
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Old 09-28-2009, 11:11 AM
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^^^^ Ya, .... what he said.

The meter reading represents SPL (sound pressure levels). Not sure how accurate it is. It really only goes to 129.9....
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Old 09-28-2009, 01:22 PM
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Originally Posted by Ramon
I have been looking around all night about how the test is done but havent found much about the way spl is tested in car trunks. I have figured out two ways, one which uses a sound meter or something and another I am not too sure about is hooking up a microphone to u r sound card and then using special software. I was just wondering how high of an spl would break window of the car.

thanks
There is no math formula to tell you how loud your vehicle is or will be. The only way to know is to test. (there are too many variables for an equation)

For similar reasons no one can say which level a windshield will break at. A lot of it depends on frequency, how well it's installed, how strong the glass is (not all windshields are created equal) as well as overall SPL.

So... the quick answer is... Gettin on the meter is the only way you'll know
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Old 09-29-2009, 11:50 AM
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I use a coin on the roof of my car to find the resonant frequency
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Old 09-29-2009, 05:38 PM
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Originally Posted by N130Gv2
^^^^ Ya, .... what he said.

The meter reading represents SPL (sound pressure levels). Not sure how accurate it is. It really only goes to 129.9....
I did not make that up actually.

Originally Posted by JordyO
There is no math formula to tell you how loud your vehicle is or will be. The only way to know is to test. (there are too many variables for an equation)

For similar reasons no one can say which level a windshield will break at. A lot of it depends on frequency, how well it's installed, how strong the glass is (not all windshields are created equal) as well as overall SPL.

So... the quick answer is... Gettin on the meter is the only way you'll know
actually there is a math formula,

behold the square derivative of the tangent function.........



that's the one I use to figure out my SPL. You can ask Peter, that's the same formula he uses.
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