Wut would 300db sound like?

[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]

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]

....

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]

I was wondering wut 300db would sound like.

Ask Bin Laden.

 

[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

jeff

 

[Wicked Klown]

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]

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

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.