SOUND SUCKER compiled and written by Amonakur and William Beaty
"ACOUSTIC
ILLUSION"
The device below is a good sound absorber. It probably absorbs certain
frequencies much better than others.
At first glance you'd think this would be boring. However, the psychological
effects are VERY INTERESTING.
When you hold the
thing up near one ear, you feel as if :
the air pressure is falling
invisible pillows are drifting around your head
your ears are about to pop
you are going deaf
your head is changing size
the size of the room is shrinking
you are about to faint
The effects AREN'T really huge, but they are significant. They seem to vary from
time to time, so if
nothing happens, try again in some other location. Also note that if you play
around with this thing for
awhile, the effects don't go instantly stop after you put it down. Perhaps it
convinces your brain that your
ears have changed shape?
INSTRUCTIONS:
Buy a couple large boxes of Dixie (tm) coffee stirrers (a few thousand total.)
These look like short, hollow,
plastic soda straws, except that they are less than 1/8" in diameter. (Don't use
the kind that look flat, they
must be round and hollow.) Obtain a straight-sided container, such as a peanut
butter jar or a tall , very
wide coffee mug. I think the straws need to seal flat against a flat surface. I
used a cardboard box with a
square of cardboard placed in the bottom. Place the stirrers in the box or jar.
Shake them around and pack
more in until you have a solid cylinder-shaped array of straws, looking like an
insect eye.
Go into a room which has significant broad-band environmental noise. Close your
eyes and bring the open
end of the straws-matrix up near one ear. Move it away. Wave it around your
head. WEEEEEIRD! Part of
the background sounds in the room are sucked up by the device, and it feels as
if your ears are filling up
with invisible cotton. You really got to try this. Sometimes nothing happens,
but when it works right, the
effect is very creepy.
JOKE:
Build two of these. Sneak up behind someone and carefully hold the open mouths
of the jars near their
ears. The victim should exhibit a strong response!
OTHER THINGS TO
TRY:
I haven't tried duplicating the effect with normal-sized drinking straws. It
might work, though the effect is
probably stronger (and higher in frequency) with the shorter, smaller diameter
straws. Also, you need to
use a fairly large diameter container, like 5" diameter or more.
IDEA: Try building
a sort of rotating "Radiometer" with several "paddles", with one surface of each
paddle covered with a drinking-straw array. One side of each paddle will act as
a reflector, while the other
behaves as a good absorber at resonance. Place a needle-bearing in the center of
the assembly so the
paddles can rotate horizontally. Now play a very loud sound in the room, with
the frequency at the resonant
absorption band of the drinking straws, and perhaps the "pinwheel" will begin to
turn because of radiation
pressure differences.
Try binding the straws together with tape or rubber bands and remove the jar.
The effect becomes much
less. Obviously a lot of sound is passing through the straws even though the
ends of the array constitute a
jump in acoustic impedance. The ends of the straws must require plugging before
the "black hole" acoustic
illusion effect occurs, so that no sound comes from the other side of the array,
and so that reflected sound is
given two chances to experience friction with the straw surfaces.
I wonder what it would be like to be near an entire wall of straws? Obtain a 2ft
cardboard box, many
thousands of coffee stirrers, then fill the bottom of the box with on-end
stirrers. Maybe trim down the edges
of the box to match the length of the straws. If the "black hole" effect seems
less, it might help to include a
wood or plexiglass plate in the bottom of the box behind the straws. This will
provide a solid acoustic
reflector ( the cardboard might be too leaky for sound.)
THEORY:
This phenomenon possibly involves the "energy sucking antenna" effect. A small
resonator, if the Q is
fairly high, will build up a strong wave which can act as "anti-sound" and
deliver energy into the resonator.
Once resonance has built up in the straws, they will efficiently absorb energy
in a region 1/4 wavelength in
all directions. They should behave like a large "pillow" which absorbs sound and
converts it into frictional
heat along the walls of the straws. This will only occur at the fundamental and
at the harmonics. The box
of straws acts as a "comb filter", and in theory it punches a series of slots in
the spectrum of broadband
noise.
After playing with
this device for many minutes, for me the "floating pillows around your head"
effect did
not stop! I put the device away and went into another room, and for about half
an hour I kept noticing
changes in my hearing, as if someone behind me was still waving the stupid
device around my ears. I've
heard that human ears are supposed to generate sound. Perhaps they employ a
feedback system, and perhaps
this plastic narrow-band absorber confuses the brain subsystem which performs my
sound localization.
Or perhaps my brain simply accomodated to the presence of the device (as when
the physical shape of our
ears is accidentally altered.) Then, when the device was removed, my acoustic
perceptions did not return
instantly to normal. The acoustic equivalent of "phantom limb effect?"
I suppose that next time I will try out one of these experiments I shall have to wear an helmet, just in case, anyhow...
I wrote this article
and tried out this experiment myself just to find out if Flanagan was saying the
truth in his article,
and much, much more.... of course...
I believe that all he said is true. Things in nature can be explained in a very
easy way.
Often scientific explanations are non sense or try to hide some information that
could be classified.
Cultural claims
often indicate the wrong direction to follow. In the article entitled "Blind can
see",
about the neurophone, it is clearly said that the pinnae or outer ear is a
"phase encoding" array that generates
a time-ratio code that is used by the brain to localize the source of sounds in
3-D space.
We have just tried out to disturb this out coming signal, and everything worked
so fine.
So, we should never forget that singing hears helps us to capture holophonic
information
that tell us much about 3d world. One ear is enough even to understand spatial
configurations properly.
So all they said is nonsense as usual.
This is the way scientific explanations go.
I guess that do it by yourself technology would be the best solution to this misleading cultural protocol.
Do it by yourself next time. It is the only advice i can give you.
Amonakur