Wut would 300db sound like?

[Mooker]

I was wondering wut 300db would sound like. Would it sound like a blower or something like that?


Thanks:confused:

[Jeff Bolton]

it would sound like an f14 doing a fly-by in your room.

jeff

[Voodoo Rufus]

It would be much worse than an F14. More like an atomic bomb blast. It would be incomprehensible, since I think 120db is where ear damage starts to kick in and the db scale is logarithmic

[Stephen Castles]

i think you wouldn't have ears anymore, or not for long :D

[ButcherUK]

130dB for ear damage I thought, 300dB would tear you limb from limb from the force of the sound waves and reduce your house to rubble too.

[Mooker]

Interesting. After wut you guys told me i'm guessing that 6 50db fans wouldnt equal 300 db, right?

[Neco]

I'm surprised the military hasn't used this as a weapon...


heh... Drop a 2000 watt 300db stereo with a tape full of white noise on the enemy:mad:

[Crazy Jayhawk]

300 dB would probably kill you. :beer:

[ButcherUK]

Originally posted by Mooker
Interesting. After wut you guys told me i'm guessing that 6 50db fans wouldnt equal 300 db, right?
No, as noted dB is a logarithmic scale, not linear. 60dB sounds twice as loud as 50dB, so six 50dB fans is in theory only about 75dB.

[Mooker]

Oh, I see. Ok thanks:beer:

[ButcherUK]

Originally posted by Neco
I'm surprised the military hasn't used this as a weapon...


heh... Drop a 2000 watt 300db stereo with a tape full of white noise on the enemy:mad:

Where would you find something capable of producing that? In a way they have found it, a device codenamed "the H-Bomb" ;)

[mw521]

Originally posted by ButcherUK


Where would you find something capable of producing that? In a way they have found it, a device codenamed "the H-Bomb" ;) They already developed this weapon, but it was banned under the "strange weapons treaty" they discovered it caused 'nad mutations so it was cruel and unusual!:beer:

[cld230]

Originally posted by ButcherUK

No, as noted dB is a logarithmic scale, not linear. 60dB sounds twice as loud as 50dB, so six 50dB fans is in theory only about 75dB.

Not exactly... an increase of 10 dB corresponds to 10x the generated sound power (ie. 10 fans would be required to increase the received sound pressure level by 10 dB). So, 6 fans would only increase things by about 8 dB.

An increase of about 6 dB is generally perceived as being "twice as loud". But, when you start making things louder, they got a lot more annoying really fast.

As far as 300 dB, it is impossible to generate a sound that loud. Shock waves form and energy is dissipated very quickly. It is called acoustic saturation. What you hear would still be loud enough to wreck your ears, but the shock wave would kill you.

[RangerJoe]

ok, hearing damage doesnt start till about 145db, my car stereo, one 12" kicker L7 with 600 watt amp will hit 140 db, and im not even powering it to the max, only reason i cant get it any higher is because my cd player skips BLAH!!!.....yes 300db you would be dead, ripped apart basically

and you all's ideas that when the sound gets up to 50db, the difference between 50-60 db is twice as much, this is kinda right, but when you get up to i think 120 db, every one db increase is twice as loud.

hey NeCo, one of my friends has one (1) 18" sub that will put out 2400 watts RMS.....and this is only a few db louder than my sub, it would take a couple hundred thousand....well prolly a couple million watts of power, running at like 1/100000000 of an ohm load.

[Wicked Klown]

Originally posted by Mooker
Interesting. After wut you guys told me i'm guessing that 6 50db fans wouldnt equal 300 db, right?


No it wouldn't equal 300db. Back when I was competing in DB Drag I was running 4 100Db amps and was noly hitting 150db. Not to mention the Explorer is (if memory serves me right) Is only between 170-180db on take off.

[Tbird man]

at that point standard speaker construction would not work i suspect you would need some sort of pezio-eletric type of speaker even than i doubt anything man could make would survive the incredible stress on the system. The milatary is experamenting with several nonliethal wepons one of which uses extreamly low frequency sound waves to casuse disorentation and even loss of bowel control.(yes their is actually a so called "brown noise") they are also testing a wepon that uses a low intensity microwave transmission to cause extreame disablitating pain (like being cooked in a micro wave)

[WyrmMaster]

Originally posted by Tbird man
at that point standard speaker construction would not work i suspect you would need some sort of pezio-eletric type of speaker even than i doubt anything man could make would survive the incredible stress on the system. The milatary is experamenting with several nonliethal wepons one of which uses extreamly low frequency sound waves to casuse disorentation and even loss of bowel control.(yes their is actually a so called "brown noise") they are also testing a wepon that uses a low intensity microwave transmission to cause extreame disablitating pain (like being cooked in a micro wave)

Yah, i have read about the microwave gun thing. I think it is planned as a riot control device. What it basicaly does is heat the skin to a very high tempeture, but only to a debth of about 1/1000 of an inch, so it doesnt really hurt you.

[Szech]

There's a bit of confusion regarding dB and dBA. 7 volts (http://www.7volts.com/quiettheory.htm) clears this up pretty well:
- dBA is a weighted curve that compensates for human perception of sound.
- A 3dB increase is about double the physical sound pressure.
- A 8-10dBA increase will double the perceived sound.

[JigPu]

Yes... Quite literaly ripped limb from limb. I believe that at appx 180dB death occours. 300dB would be so insanely loud, a 10dB increase (as has been mentioned many times before) doubles the power of the sound wave. So, 300-180=120dB. So basicaly, you are looking at 2^12 (4096) times as powerfull a wave.

Now be thankful you Delta is nowhere near that loud :)
JigPu

[Wicked Klown]

Originally posted by JigPu
Yes... Quite literaly ripped limb from limb. I believe that at appx 180dB death occours. 300dB would be so insanely loud, a 10dB increase (as has been mentioned many times before) doubles the power of the sound wave. So, 300-180=120dB. So basicaly, you are looking at 2^12 (4096) times as powerfull a wave.

Now be thankful you Delta is nowhere near that loud :)
JigPu




Not really death can occur at around 120-130db`s depends on how low the Hertz are. Mine at full blast at 1hertz could stop a heart.

[PsYko420]

Well a regul;ar jet airplane taking off is around 140 db from like 100 ft away and thats pretty freaking loud so like jigpu said times that by around 4000 and well theres no more you....

[RangerJoe]

i belive kicker in their competitions has gotten up to 176.5db or something like that, a new record for stereos

edit: make that 171.1 db...my bad

[Diggrr]

In the weapon they're testing for low frequency, they use a chamber with a constant feed of propane. The spark plug in it fires at the desired frequency. This sound force is propelled out of 6 or 8 holes in one end into a feed horn.
It got the the name brown noise from the effect it has on people...you don't wanna fight much when you're all sh***y!

Doesn't anyone watch Discovery channel?

As for the fans, add all you want, but the panaflo L1A's are the quitest I've found. Checkout www.caseetc.com. That's where I got mine with only 3 days delivery time UPS. Both the PSU and the harddrives are louder than my 120mm. For that fan, you can quiet it down more with a 35ohm, 5watt resistor, or a potentiometer if you'd like.

The 5 watter's have heat sinks on em (cool) and it's the only heat sink in my case........give me that cold clear water baby!

[Gravity Man]

I'mnot 100% sure, but I wouldn't doubt it-- I did some research, and according to my math skills at 2:00 AM and my trusty hewlett packard 48GX calculator, 300 Db would be 2.901999 x 10^291 PSI:eek:

[Wicked Klown]

Originally posted by RangerJoe
i belive kicker in their competitions has gotten up to 176.5db or something like that, a new record for stereos

edit: make that 171.1 db...my bad



The world record is 179.9db. It was made by Team Gates.

[Yodums]

That would make like planes in your house and getting the neighbours flaming you!

[oc jason]

Heck i had a buddy that placed 7th in the World IASCA, form Streo One, Fayettville, AR..

65 VW Bug, 16 "10" JL Audio subs, like 7000watts, it was 165db, and when i sat in it and set my soda on the dash , a guy from an exterior control panel, cranked it up and it rattled the molding out of the doors, and after the soda bounced off the windows needless to say i was wearing it... That in itself was insanely loud, 179 db by Alma Gates i dont even wanna hear that.

I mean to get a 3db increase it had to double the spl, (sound pressure level) and for a 8db increase it is like double the perceived sound level. so to sit in a area with 179 db would be 14db more than the car i sat in, making that almost 2x louder than a car, whose sound waves threw things on the dash into the windsheild....that is loud.

300db.....lol that is amazing to just think about, i mean if and when the big bang theroy ever really happened it probly was not 300db, i dont think that kinda sound had been or even will be heard in this universe, but at that level i think itd tear the universe apart

[oc jason]

Originally posted by mw521
They already developed this weapon, but it was banned under the "strange weapons treaty" they discovered it caused 'nad mutations so it was cruel and unusual!:beer:

Are you talking about the Hydrogen bomb, well i had actually looked into that while in High School, and it is not a sound producing weapon, it is like and atomic bomb, just that is splits atoms of Hydrogen. sililar effect, more radiation.

And get this there is soemthing like 4 Cobalt Bombs, they have made and can never use unless they wanna new planet. Im not a chemist, but it said it would react with all the gases in the atmosphere, therfore demolishing the entire playnet in like 14 minutes.

that was just read by me in Popular Science while in High School, it could be complete BS

[Intraveinous]

Originally posted by oc jason


Are you talking about the Hydrogen bomb, well i had actually looked into that while in High School, and it is not a sound producing weapon, it is like and atomic bomb, just that is splits atoms of Hydrogen. sililar effect, more radiation.

And get this there is soemthing like 4 Cobalt Bombs, they have made and can never use unless they wanna new planet. Im not a chemist, but it said it would react with all the gases in the atmosphere, therfore demolishing the entire playnet in like 14 minutes.

that was just read by me in Popular Science while in High School, it could be complete BS

Semi-right on the H-Bomb... It uses isotopes of hydrogen injected into the fission reaction to start fusion. So in addition to splitting atoms of Plutonium and Uranium, it's fusing atoms of Hydrogen into helium. It produces more energy and hence more destruction. As far as Cobalt Bombs and other "dirty bombs" go, they work based on the halflife of the dopant. Cobalt is poison to pretty much all living things for several (hundred?) thousand years... Pretty much so long that it makes the area hit by the bomb completely worthless forever in our short lifetimes. It would be many generations before it could be used at all, and would probably still be dangerous after that. I'm not sure about reacting with gasses in the atmosphere, it's plausible, though I haven't heard of that with cobalt bombs.
All from memory, so I too could be wrong.
peace
John

[Crash893]

i hear the (ch)air force buitl a 3 story sub woofer with a funnle on it ( to concentrate teh sound ) to test the effects off sonic booms on a house

anybody know anything about this i ( im trying to find the article now it was in a pop sience)

[Intraveinous]

I do remember reading something like that... I'll join your search for the article.
Peace
John

Edit: Well... It looks like they don't do it that way anymore... found this:

AHPCRC Preprint 95-003: A data parallel TVD method for sonic boom calculations
by: A. Pilon and A. Lyrintzis
ABSTRACT: Sonic boom predictions are shown for the near- and mid-field, and comparisons are made with experimental data. The computations are performed on the Thinking Machines' CM-5 massively parallel supercomputer to utilize its large available memory and high floating point performance. A second order accurate total variation diminishing scheme is used to solve the Euler equations in the computations. Additionally, a recently developed implicit method, based on the LU-SGS algorithm, is used to speed the convergence and accuracy of the steady state computations. The method is shown to work well on near- and mid-field sonic boom predictions for several test cases.

Who needs real life when you can simulate it on a supercomputer. :D
Peace
John

[Silversinksam]

You wouldn't want to be exposed to 300dB

Approx. dB level
Examples

0
The Quietest sound you can hear

20
Whisper, quiet library

65
Normal conversation, sewing machine, typewriter

90
Lawnmower, shop tools, truck traffic; 8 hours per day is the maximum exposure (protects 90% of people.

110
Chainsaw, pneumatic drill, snowmobile; 2 hours per day is the maximum exposure without protection.

115
Sandblasting, loud rock concert, auto horn; 15 minutes per day is the maximum exposure without protection.

140
Gun muzzle blast. jet engine; noise causes pain and even brief exposure injures unprotected ears. Maximum allowed noise with hearing protector.


http://www.howardleight.com/Industrial/education/NoiseLevelsAndFrequency.html




OSHA's levels are slightly different:

95 dB - 4 hours
100 dB - 2 hours
110 dB - 30 minutes
120 dB - 7.5 minutes

[Christoph]

Concerning the atomic bomb, it's not a sound weapon as such, but it does produce a very intense shock wave (can I assume that most of you have seen that film of a house hit by the shock wave from an atomic bomb). The major practical difference between a sound bomb and an atomic bomb of equal intensity, AFAIK, is the radioactive crud that gets everywhere.
Does anyone know of some way to convert equivalent megatons of TNT into dB?


BTW, did anyone else have just a little trouble understanding that supercomputer abstract?

[Wicked Klown]

[QUOTE]Originally posted by oc jason
[B]Heck i had a buddy that placed 7th in the World IASCA, form Streo One, Fayettville, AR..

I have a friend who placed 7th this year at the world finals. Back
in 99 he placed first.

[cld230]

Originally posted by IdeaMagnate
BTW, did anyone else have just a little trouble understanding that supercomputer abstract?

If you want to understand it, here are a few clarifications...

They made some measurements on sonic booms at some time and have a computer model that they are comparing to them. The notion of near-, mid- and far-field are not always well defined in acoustics, but are a function of frequency and the size of the source. Simply knowing that the model matches over some range is all that is really important from that.

The 2nd order accurate total variation diminishing scheme would imply that non-linear effects are taken into account. This is sort of a given, as shock waves are non-linear effects. (In most acoustic problems, a linearized wave equation is used, and higher order effects are ignored) The Euler equation is a fundamental equation in fluid dynamics and acoustics.

The rest of what they say just implies that they have come up with a good way to make their model converge to a solution in some sort of efficient manner. I don't know anything about the LU-SGS algorithm.

Okay, perhaps I didn't clarify anything, but I think that point is that this computer model does a good job of modeling sonic booms under the conditions that these people were dealing with.

[Christoph]

Thanks. It's much clearer what's going on now.

[SteenkyBastage]

140 DB for gunshots? ugh...

i fire pistols quite a bit, and out at the range i dont even wear earplugs all the time. i had a p90 (.45 pistol) that was bearable when i shot it at the firing range.

but i later found out the error of my ways...

hiking thru the mountains in alaska, i saw a groundhog-type-thingie that was actin pretty bold and not runnin away like most critters do. now, this is in a valley with a bridge running over a 75 foot or so sheer cliff sides to the canyon.

well, i fired the handcannon at the poor li'll bugger and couldn't hear anything for at least 15 minutes. my friend was yelling at me from across the river (maybe 50 ft.) and i couldn't hear a thing... just a niiiiiiiice LOUD ringing.

the moral of the story... dont let evil little critters make you sabotage your hearing, tempting as it may be...

i have no idea how many DB that would be, but it was extremely loud and painful.

[CrystalMethod]

My friend had a some of "ear-piercer" sirens in his car (part of an alarm system). They're actually illegal in Canada (I don't know about the U.S.), but they put out a whopping 337Db. They are meant to rupture your eardrums, and will actually cause your ears to bleed. The funny thing was that he sold the car and forgot he had installed 3 of them and only removed 2. He was in a panic for 3 days trying to get hold of the guy that had bought his car, so he could warn him and remove the last siren before anything happened. Luckily the new owner of the car hadn't tripped the alarm accidentally and my friend managed to explain the situation and was allowed to remove it before anything happened. So i'm figuring that 300Db would pretty much do the same thing to your ears.

[Wicked Klown]

[QUOTE]Originally posted by CrystalMethod
[B]My friend had a some of "ear-piercer" sirens in his car (part of an alarm system). They're actually illegal in Canada (I don't know about the U.S.), but they put out a whopping 337Db. They are meant to rupture your eardrums, and will actually cause your ears to bleed.


Not that I'm saying your wrong , but as far as I can remember they don't have a machine out yet that can go up to 337db. I do find this a little hard to belive and I'm sure other will as well.

[Christoph]

That would break more than just an eardrum or two, it would totally destroy the car. Even half of that is dangerous (which means a BIG change considering that 8 dB +/- doubles the perceived intensity).

[Slain]

You forgot that the damage to the human body depends very much on frequency.

You are quite safe at 150dB at 50 Hz but you would be permenantly deafened at a frenquency of 5KHz.

^^

[cld230]

The manufacturer may claim some incredibly high SPL for your alarm, but I would be very suspicious. One thing to consider is that sound waves are a result of pressure variations in the atmosphere. Considering an atmospheric pressure of 101.3 kPA, the SPL if the minimum pressure that is attainable is a complete vacuum is 191 dB.

Sound pressure levels are also a received level at some specific location. A sound power level is an indication of the acoustic power that a source is producing.

If the manufacturer is claiming a sound power level of 337 dB, that is 5*10^21 W of power that is coming from your source. This is obviously not possible. My guess is that somewhere along the way 137 dB got turned into 337 dB.

As a side note, there is a phenomenon in non-linear (ie. very high amplitude) acoustics that is called acoustic saturation. In basic terms, shock waves dissipate energy, and the bigger the shock, the more energy is dissipated. At a high enough drive amplitude from your source, the increased energy that your source puts out is offset by the increased energy loss in the shock wave, and the receiver level will not increase. The level is a function of frequency and distance from the source among other things, but there is a point where you can keep turning up the volume and gain nothing.

As an aside, I don't really know how sound level meters perform once the sound pressure levels start getting very high, but this is generally out of spec for most SLMs, and the readings are likely questionable at best unless someone is using a very very high end meter.

So, if someone starts quoting sound pressure levels for some sound source in air that are above 200 dB, I would really have a hard time accepting that.

[HiProfile]

At 300db, I think the air would literally become [if only of an instant] as dense as liquid, as sound is just the de/compression of air [and other matter].

As for those alarm horns, would also add that 137db would seem right, since thats around the limit for alarms in USA (130db-135db?).

One last thing I can add is that our government set up a HUGE 1 BILLION watt subwofer to simulate small earthquakes (how else can we get rid of Canada?). If low-freq sound can make you s*** in your pants, this should do it!

[Silversinksam]

Originally posted by CrystalMethod
My friend had a some of "ear-piercer" sirens in his car (part of an alarm system). They're actually illegal in Canada (I don't know about the U.S.), but they put out a whopping 337Db.


Crystal,

I think your friend's claim that its 337dB is very far fetched, As that's basicly Impossible for a car alarm to reach that noise


The space shuttle puts out 175dB (SPL)sound pressure level and 200(dB) PWL sound power level in the 50 foot radius of the blast zone and there's no way a Car alarm is louder than the Space shuttle's Launch.

And trust me Ive been in the VIP area at Kennedy during a couple launches and its pretty dang loud and the VIP area is pretty far from the pad.

[oc jason]

ya at 337db, usually a car alarm would be pretty hihg like 10khz, or so. So that would jsut rip the metal off of the car. Man 300 or more db, would just be a catastopic disater.

[ButcherUK]

10 KHz is probably too high for an alarm most would be 2-5 KHz I'd think.

[Christoph]

Originally posted by Silversinksam



....

And trust me Ive been in the VIP area at Kennedy during a couple launches and its pretty dang loud and the VIP area is pretty far from the pad.

dr0000000000000l.

[Wicked Klown]

Correct me if I'm wrong but at 337db and say 5KHz wouldn't the windows shatter.

[KeyboardCowboy]

the world record at a db drag (car audio) is somethine like 183.7db, for a stereo mounted in a car, i had the pleasure of seeing this thing, it was insane, high strength bullet proff Lexan insted of glass and mirrors, carbon fibre insted of plastic dash, seats that were bolted down with tugsten carbide bolts, all this so that when it was pumping out 180+ db it wouldn't blow itself apart, for saftey the car stereo was controlled from 75 feet away by remote


300db? that would make your ears bleed, and probally pop your head like a zit

[Slain]

Just thought of a place you could possibly reach 300dB. The largest explosion possible in this universe is the collision of 2 black holes. Due to the immense density of the matter present, shock wave loss would be neglible and the energy transmmited un-imaginable. Could come close to 300dB?

[Colin]

Originally posted by Mooker
I was wondering wut 300db would sound like.

Ask Bin Laden. :D

[Tbird man]

HAHAHAHA!!!!! GOOD ONE HEHEHE BIN LADEN HOHOHOHO! THATS TOO MUCH!!!!!!!!!!!!!!!!!!!!.............umm heh yeah so i as i was saying...what was i saying again...oh yeah i think 300 db would probibly cause a massive pressure wave strong enough to make you and everything close by vaporise from the heat generated (when things compress they heat up)

[Jeff Bolton]

all this talk reminds me of lectures i've heard about the civil war...the solid shot would fly by people's heads at such high speed that the vacuum behind it would create whatever was near to it to get seriously f'd up. anyone seen glory? the guys head blew right up when the cannon ball passed his head.

not really on the subject just cool :D

jeff

[Wicked Klown]

Originally posted by KeyboardCowboy
the world record at a db drag (car audio) is somethine like 183.7db, for a stereo mounted in a car, i had the pleasure of seeing this thing, it was insane, high strength bullet proff Lexan insted of glass and mirrors, carbon fibre insted of plastic dash, seats that were bolted down with tugsten carbide bolts, all this so that when it was pumping out 180+ db it wouldn't blow itself apart, for saftey the car stereo was controlled from 75 feet away by remote


300db? that would make your ears bleed, and probally pop your head like a zit


What Team was it? Cause when I was there and when I competed you were right next to your car. Sometimes there were even people on your car.

[CrystalMethod]

337db is just what the package said on it, but who the hell is going to test the theory at ground zero? We never had the guts to be in the car when it was set off. When we installed them, we put in earplugs and stood about 50 yards from the car with it's doors and trunk open and then triggered the alarm through the remote. The noise was this incredible shriek, not even sure how to describe it. It was definately not in the low end of the spectrum. After breaking out the old sound text books I came across a bit that may explain how teh company that sold the sirens was able to advertise them at the the 337db rating.
"Not all sound pressures are equally loud. This is because the human ear does not respond equally to all frequencies: we are much more sensitive to sounds in the frequency range about 1 kHz to 4 kHz than to very low or high frequency sounds. For this reason, sound meters are usually fitted with a filter whose response to frequency is a bit like that of the human ear. (More about these filters below.) ...
...The most widely used sound level filter is the A scale, which roughly corresponds to the inverse of the 40 dB (at 1 kHz) equal-loudness curve. The sound meter is thus less sensitive to very high and very low frequencies. Measurements made on this scale are expressed as dBA. The C scale is practically linear over several octaves and is thus suitable for subjective measurements only for very high sound levels. Measurements made on this scale are expressed as dBC. There is also a (rarely used) B weighting scale, intermediate between A and C"

They could have measured them at a range close enough to give them a super high reading and used one of the two less common scales to give them an "legit" reading that they could stamp on the package. I'm not saying that they actually did go up to 337db, but it was loud enough at the time for us to belive it.

[Christoph]

Originally posted by Spike Spiegel
all this talk reminds me of lectures i've heard about the civil war...the solid shot would fly by people's heads at such high speed that the vacuum behind it would create whatever was near to it to get seriously f'd up. anyone seen glory? the guys head blew right up when the cannon ball passed his head.

not really on the subject just cool :D

jeff

I wouldn't exactly call it cool when real people's heads explode (as opposed to fragging your best friend after school). Massive forces have a special appeal to the male mind (I've got one, I should know). That a cannonball can do that is cool. That it does isn't, IMHO.

[supraway]

I don't know how much of everything is legit... anything over like 200db would maybe even kill a person. About the car stereo that does 140db... have you ever had it tested? Mine has a 300w Pioneer amp driving a Ultimate 10" sub, along with 150 watt Kenwood Excelon front speakers, only puts out about ~115 max db's. I dunno... 140 seems high out of one 12" sub... Speaking of, Canada has a couple of crazy guys who built a sound system in a compact car... 58 or so 8" Rockford Fosgate subs, and like 10000 watts total. I'm not exactly sure what everything was. They had to have a 500 pound battery custom made for their car, and it would even only last 1 minute at max volume. Total db: 165

[CrystalMethod]

I think that car is here in Montreal. There is a performance stereo place here that stuffed 10 12" subs in a Ford Aspire (not sure why they chose that model). The thing was louder than hell. Got lots of attention though, so as a marketing tool, so I geuss it worked. How did this subject come up in "Cooling" anyways?

[Wicked Klown]

One of the best cars I even seen was my buddies car. The Rockfard Fosgate Team White Wolf van. Last I heard he hit like 170db at 36,000+ watts.

[Silversinksam]

There is no way the manufacturer printed 337dB on the box as that would leave them open to lawsuits and the like.

All it would take is one bystander near the car when it went off to say that his hearing was affected and that company would be outta business so fast it wouldnt be funny.


And if the company did Imprint a 337dB rating on it they are blooming idiots and will be sued sooner or later.

[cld230]

Originally posted by CrystalMethod
They could have measured them at a range close enough to give them a super high reading and used one of the two less common scales to give them an "legit" reading that they could stamp on the package. I'm not saying that they actually did go up to 337db, but it was loud enough at the time for us to belive it.

A-weighting a sound pressure level results in a decrease in the reported SPL. The idea is that at low and high frequencies, and at low levels, your ear doesn't hear sounds nearly as well as in middle frequency bands (over the frequency range that is important in understanding speech).

What people here seem to be not understanding is that a sound pressure level of 337 dB is IMPOSSIBLE. A sound pressure level of 337 dB corresponds to an RMS pressure variation of roughly 14 million times atmospheric pressure or a peak pressure amplitude of 20 million times atmospheric pressure. So, we create a vacuum, keep sucking nothing out of it to make some sort of magical place where there is 20 million times less nothing. Then we manage to pressure up to 20 million times atmospheric pressure, and repeat at whatever frequency we are operating at.

I think not.

[JigPu]

Not sure how you got your math there, but if it's right, thats some impressive sound levels!! Definatly capable of liquifying (at the very least...) the air!

I know you are wrong on one point though. It wouldn't be 20 million times nothing for the low side, it would 1/20,000,000 of atmospheric pressure. Of course, that is still extremely low. Lemme see here...

1 atmosphere is 101,325 Pascals (1 newton / square meter). 1/20,000,000 of that is 0.00506625 Pascal (0.0001058 pounds/square foot). That's some LOW pressure! :eek: Sounds worse than that cannon you guys were talking about!!

JigPu

[cdrikari]

Originally posted by IdeaMagnate
Does anyone know of some way to convert equivalent megatons of TNT into dB?


One could make a decent guesstimate of it by looking up what the overpressure wave from a large nuclear blast is and then doing the math to figure out what an equivalent dB would be. Bear in mind that while this number is probably impressive, it is dB, not dBA and as such it is hard to tell what a nuclear blast sounds like at the point where the shock wave generates the maximum overpressure.

Setting up a relationship between dB and Mt would be harder since the relationship between (for instance) a 100kT bomb and a 1MT bomb is hardly linear. As you get into the MT range you really face a law of diminishing returns. A 1MT bomb is not 10 times as powerful as a 100kT bomb.

[cld230]

Originally posted by JigPu
Not sure how you got your math there, but if it's right, thats some impressive sound levels!! Definatly capable of liquifying (at the very least...) the air!


SPL = 20*log(P/Pref)
Pref = 20*10^-6 for SPL in air

This gives the RMS pressure, so multiply by sqrt(2) to get the peak pressure amplitude.

This gives that magnitude of pressure above and below atmospheric pressure, and for a sine wave input, you have a pressure increase and pressure decease that are symmetrical (according to a simple linear model of sound waves), and we have already concluded that the pressure swings are much larger than atmospheric pressure, so the resulting sound wave would have negative pressures.

[DarkInferno_IV]

300DB would be more intense than being at Ground Zero of a fusion bomb blast. It would literally vaporise you, before your brain even registered the sound you would be reduced to your constituent molecules.

Sorry, you will never hear 300DB:-)

[CrystalMethod]

Like I said it's just what was on the package when we installed the thing. I wasn't my alarm, so I had no say in what my friend bought. He just showed up with these things and asked me to help him install them.
300DB would be more intense than being at Ground Zero of a fusion bomb blast. It would literally vaporise you, before your brain even registered the sound you would be reduced to your constituent molecules.


..so it comes back down to the question of "If a fusion bomb goes off, and vaporizes everyone around, does it still make a sound?"

[SteenkyBastage]

no, the real question is...

if a fusion bomb goes off in a forest, and causes a tree to fall...but nobody's around, does it still make a sound?

[mw521]

The best thing is you would only listen to it a sec or two, then you wouldn't have to/couldn't hear it anymore.:beer:

[Tbird man]

"a sound pressure level of 337 dB is IMPOSSIBLE"

So was sailing to Inda, and flying, and splitting atoms.
Remember just beacuse we do not know how it is done dosen't mean it can not be. Though I will agree it is mathmaticly improbible, nothing is impossible.

[Christoph]

This is the second strangest thread I've ever seen.

[Silversinksam]

So Basicly your saying your friends car is equipted to handle almost twice the Db's of this van which is Bulletproof to withstand its max of 164 db



Look here (http://cgi.ebay.com/ebaymotors/aw-cgi/ebayISAPI.dll?ViewItem&item=598967080&r=0&t=0)


http://europa.your-site.com/~dr.z/pictures/van1.jpg



300DdB is Impossible for a car alarm to achieve my friend.


;)