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Spud McLaren
1023932.  Sun Sep 22, 2013 4:33 pm Reply with quote

Here is a list of some of the loudest noises known.

These have been measured in decibels, and it is interesting to note that the decibel scale is used in more than just sound power levels, and doesn't work in quite the way most people seem to think it does. Approximately, for every increase of 3 decibels, power level doubles - so an increase of 10 db is a tenfold increase in power, and a 20 db increase is a hundredfold increase in power.

Decibel link

 
CharliesDragon
1023939.  Sun Sep 22, 2013 4:55 pm Reply with quote

I really, really, really don't like loud noises. *Curls up in fetal position and covers ears with hands*

We could expand on the subject as to if there's a fancy name for disliking loud noises or if there's been studies of how much noise people from different places think are too much?

 
Spud McLaren
1023940.  Sun Sep 22, 2013 4:57 pm Reply with quote

Go for it.

 
Elz Bellz!
1023942.  Sun Sep 22, 2013 5:03 pm Reply with quote

CharliesDragon wrote:
We could expand on the subject as to if there's a fancy name for disliking loud noises.


Ligyrophobia.

Hurrah, I beat Suze to a fancy word!

 
CharliesDragon
1023949.  Sun Sep 22, 2013 5:48 pm Reply with quote

Yay, Elz! (Also, your username is clever. I approve.)

And Spud, I was more hoping someone already had the information. I'm far too lazy to find it myself, much less understand it and convey it correctly. I've come to the conclusion I fit best in the back row, listening to the rest of you being smart.

 
Webster100
1023971.  Sun Sep 22, 2013 9:50 pm Reply with quote

Quote:
5. The Blue Whale


Oh boy...

 
ConorOberstIsGo
1041805.  Tue Dec 17, 2013 2:58 pm Reply with quote

So would the show ask a L-l-l-logarithmic question?

e.g.
Q: A passing lorry is 75 decibels so how loud is the sound of two passing lorries?

K: 150 decibels

A: About 77 decibels.

it's not great as a question but perhaps we can think up a creative way to deliver it?

 
djgordy
1041815.  Tue Dec 17, 2013 3:41 pm Reply with quote

Quote:
The erstwhile NME journalist Charles Shaar Murray once told a story of the most wasted night of his life. He said that the last thing he remembered was being at a Motorhead concert, sticking his head in a bass bin and shouting 'louder, louder'.


www.bbc.co.uk/dna/mbpointsofview/html/F2107879?thread=1227509

Probably my favourite rock'n'roll story ever.

 
PDR
1041897.  Tue Dec 17, 2013 7:15 pm Reply with quote

ConorOberstIsGo wrote:
So would the show ask a L-l-l-logarithmic question?

e.g.
Q: A passing lorry is 75 decibels so how loud is the sound of two passing lorries?

K: 150 decibels

A: About 77 decibels.

it's not great as a question but perhaps we can think up a creative way to deliver it?


It's a rather dodgy question though, isn't it? The question is delving to a technical level on the nature of logarithmic scales and sound power, but risks being shot down over the way it over-simplifies the cumulative effect of sound propagation.

Firstly sound is never measured in "dB" - it's measured against a specific dB scale like dB(A) or dB(NA), each of which has a different frequency weighting envelope (pure dB can only be used to compare two things relative to eachother).

Secondly the two lorries would have to be in exactly the same place at the same time for their sound emissions to sum in that way. This is impossible, and one would have to be behind the other. This would put the second in the slipstream of the first and thereby eliminate about 30% of its total sound emissions (which are aerodynamic not exhaust, gearbox or tyre noise).

Even if we assume the two lorries were identical, so they ran at the same RPM giving the same frequency spectrum of noise, they would create zones of constructive and destructive interference, so the sound levels would rapidly rise and fall in the perception of the fixed observer (you do sometimes experience this effect when standing next to a busy road).

dB scales are used extensively in analogue electronics and radio/radar engineering because they are so generally useful.

PDR

 
suze
1041908.  Tue Dec 17, 2013 8:16 pm Reply with quote

PDR wrote:
Firstly sound is never measured in "dB" - it's measured against a specific dB scale like dB(A) or dB(NA), each of which has a different frequency weighting envelope (pure dB can only be used to compare two things relative to eachother).


This is of course true - the decibel is a relative rather than an absolute unit.

But the layperson has only encountered it as a unit of "loudness" (properly, sound pressure), and I have to confess that I had a Masters degree and had spent a reasonable number of hours messing about with oscilloscopes before I knew that it could be anything else.

Because the scale is logarithmic, the definition of zero is tricksy. Defining zero decibels as some notional complete silence would make the math more complicated than necessary, so that isn't how it's done. 0 dB was instead defined as the minimum sound level of a pure tone at 1,000 Hz which an "average human ear" with "undamaged hearing" can hear in the absence of other audible sounds. (There are lengthy formal definitions of the two bits in quotes.)

There are problems with this, though. For a start, most adults can't actually hear the prescribed tone. (I can't, although I can hear a sound at the same level if the tone is 2,000 Hz. At least, I could last time I tried.) And some people - usually prepubescent girls - can hear a quieter sound, so negative values have to be allowed.

But it was discovered by experiment that the zero decibel sound has a sound pressure of almost exactly 0.00002 Pascals (RMS). Which is therefore by now used as the definition in most circumstances.

 
EXE
1043893.  Thu Dec 26, 2013 8:27 pm Reply with quote

Some of these unexplained noises are pretty creepy (especially if you imagine yourself hearing them alone in a bathysphere deep in the ocean). Also, some of the sounds on that list have pretty great names.

 
krollo
1044053.  Fri Dec 27, 2013 2:02 pm Reply with quote

EXE wrote:
Some of these unexplained noises are pretty creepy (especially if you imagine yourself hearing them alone in a bathysphere deep in the ocean). Also, some of the sounds on that list have pretty great names.


The link to the 52-hertz whale is quite interesting but also quite sad. :-(

Also, check out the Electronic voice phenomenon. Not to mention the brown note, which alas was proven nonexistent in the 1970s. I'm surprised to see Ob-la-di Ob-la-da on the list of worst songs ever though - surely it isn't that bad?

 
EXE
1044065.  Fri Dec 27, 2013 2:33 pm Reply with quote

krollo wrote:
The link to the 52-hertz whale is quite interesting but also quite sad. :-(


I know, especially where it says that it "has been described as the world's loneliest whale." I wonder how stiff the competition was.

They did an episode of The Mythbusters about the "brown note."

Speaking of colors and noise, a lot of people know about white noise, but there's also pink, red, blue, azure, violet, and grey noise (source).

 

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