h a l f b a k e r y
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
or get an account
I was recently watching a documentary about Krakatoa.
Not only has the place
moved (it isn't East of Java), but it was also purportedly the
loudest noise ever
heard by human ears.
This simply isn't good enough. It puts human ingenuity to
shame, if the most
extreme of anything is a natural
phenomenon. We don't
tolerate it for speed
(except for light), tensile strength or coldness. So it's
really time to see if we can't
improve on Krakatoa.
What I propose, therefore, is a national effort (preferably
by Belgium, since they
deserve to be known for at least one thing) to create the
loudest sound ever heard
Of course, a big enough nuclear bomb detonated in a large
dustbin would be the
obvious way to go, but that's far too simplistic and, besides,
Belgium does not
Therefore, I think we should go for the loudest *sustained*
sound ever heard on
In the first instance, I think that some sort of vast,
megalithic vuvuzela might be
the way to go. Propulsion would have to come from
enormous reservoirs of
compressed air - possibly created by hollowing out large
areas of the Earth's crust
directly beneath Belgium. Mine shafts would connect these
reservoirs to the
instrument itself, which would either occupy a considerable
portion of Belgium or
(and this is the clever bit) could also be sculpted directly
out of the bedrock.
With some clever musicogeological engineering, I am sure
that a stratum of granite
could be used as the main resonator in the instrument.
Obviously, the instrument would need some form of bell or
horn to project the
sound; this would have to be carved into the ground as a
depression, or could in theory be constructed above ground
concrete. Given the size of the bell, and the fact that it
would probably point
upward, it would be important to plan this as a summer
project when significant
rainfall is not expected.
Scaling laws suggest that the frequency of such an
instrument might be below the
threshold of human hearing. Howevertheless, it should be
possible to monitor the
success and amplitude of this device using balloon-tethered
Alternatively, large flocks of birds could be released above
the instrument; the
infrasound waves would then be made visible as
compression and rarefaction of the
P.S. Once Belgium accomplishes this feat, other nations
will be queueing up to exceed it. For countries on tectonic
plate boundaries (especially subduction zones, where one
plate is diving under another instead of just sliding
sideways against it), it ought to be possible to construct
long parallel artificial mountain ranges along the fault line.
Subduction would then produce a phenomanally low-
frequency, high-amplitude sound. If commercial
sponsorship is needed, the mountain ranges could be of a
spacing and profile such that they played the sponsor's
sound-logo over a period of several tens of millions of
Apparently one of those serendipitous typos that was allowed to stay - like the one which re-titled "A Clockwork Orang". [pertinax, Jun 01 2015]
[hippo, Jun 01 2015]
||How do they define "loudest"? Because there is a functional
upper limit to volume, which is the point where the
rarefaction portion of the sound wave is perfect vacuum
(194 dB at STP).
||//How do they define "loudest"?//
||Presumably one also has to consider the positive
pressure at the peaks of the sound wave; a limit
there would be imposed by the tendency of air to
liquify at high enough pressures.
||There's also the question of distance from the source.
Krakatoa was allegedly heard in England. Therefore,
it might be necessary to set up monitoring stations
around the world.
||In any case, my definition of "loudest" is "like
Krakatoa but more".
||I dont think Krakatoa was the loudest thing that
nature has done. The origin of the universe,
commonly known as the Big Bang, was, by all
accounts, a big bang maybe the biggest. What
youd have to do is beat that, probably by origining
another universe, only bigger.
||//Krakatoa was allegedly heard in England//
||Have you considered the fact that this was not the loudness
of Krakatoa, more the astounding sensitivity of some of
England's most talented killjoys? Like the Princess and the
Pea, only with moany old battleaxes and social gatherings of
Macclesfield's more sophisticated teenagers.
||//the Big Bang, was, by all accounts, a big bang//
||Ah, yes, but that happened in space. And in space,
no-one can hear you.
||If, after construction of such a large soundermaker,
Yellowstone decides to go up, will we have hollowed out
Belgium for nothing?
||Is here the place to talk about what Belgium is known for?
||Well, we say that in space nobody can hear you, but I
dont think thats entirely true. Partly because were
fooled into thinking that acoustics depend on air
transmission, and theres no air and therefore no
mechanical medium for acoustic signals. Partly
because all the films weve seen (particularly the
ones with space scenes in them, not so much the
cowboy films or historical rom-coms) have a scene
where the audio is either cut for the EVA long shots,
or replaced with a music bed over dramatic silence.
||I think it should be possible to detect acoustic effects
through space, even though science tells us that its
impossible. This is one of many of those instances
where we think its impossible but were really not
trying hard enough. We should be able to detect
evidence of sound transmission through space, if only
we tried harder.
||It needs to say BOOOOHHHH!!!
||//detect acoustic effects through space// The laser
signal bounced off the reflectors on the moon (when
people could go to the moon) contains seismic sound
Loudness is a perceptual term, indicating psycho-
acoustically perceived sound amplitude. The
physical correlate is acoustic amplitude, usually
measured as sound pressure, or the logarithmic
Sound Pressure level (SPL.)
||So, a Very Loud Noise will be observer dependent,
up to but not including the death of the observer.
||Yes. However, the Very Loud Noise about which we
are talking here will just be loud, period. It will be
so loud that, even if there is no-one there to hear it,
it will still cause trees to fall over.
||How about a very lout noise - oi!..... or a very loud nose, or a fairy louse noise... eeeek.
||I'm pretty certain liquid is an effective medium to
transmit sound in.
||Sadly liquids also suffer abrupt limits in wave energy
transmission due to the tendency to cavitate.
||If the outer bounds of our atmosphere were to be
considered as a spherical diaphragm, and other
planets with atmospheres were similarly diaphragm-
like in acoustic behaviour, then all it takes is some
other transmission medium in-between the two
planets to be able to hear interplanetarily. What is
that medium? Well, thats an entirely different
||//what's the medium?// - the message of course.
||To avoid the vacuum/cavitation limit, pressurise the whole
system. Probably Jupiter would be useful at this point.
||// Given the size of the bell // Whistle?
||// pressurise the whole system//
||Actually that's not a bad idea.
||////what's the medium?// - the message of course.//
||Baked (in fiction) - weren't Disaster Area's concerts the loudest sounds ever made (see link)?
||Also: Question - if the Belgians make the loudest noise ever,
but everybody goes deaf and nobody ever hears it, was that
sound a sound?
||//Presumably one also has to consider the positive pressure
at the peaks of the sound wave//
||Not really. Once you have a vaccum in the rarefied portion,
the pressure portion maxes out as well. Anything beyond
that point becomes a single shock wave, pushing the air in
front of it, rather than vibrating.
||One approach could be to have multiple simultaneous
volcano eruptions worldwide. A further step may be
to modulate this combined volcano carrier signal with
the sound of something even louder.
||The big bang was audible; see: microwave background radiation.
||an explosion big enough to cause the entire universe to heat
up 3 degrees is pretty loud.
||Isn't the whole point to have a large?