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> hey anon, wanna give your opinion?
asd
User avatar #468 - Welshhobo
Reply +5 123456789123345869
(05/19/2013) [-]
For those interested in how it works (my dissertation is finally coming in some use ).

When a sound is created in an enclosed space, it will reach out to the edges of this space. Upon hitting the edges, it will do two things – reflect, and be absorbed through transmission. Depending on the smoothness of a surface, the ratio between absorption and reflection can differ. This paragraph sums up absorption and reflection well.

“All surfaces absorb some energy, reflecting the remainder back into space, the amount being reflected or absorbed being determined by the physical properties and shape of the surface material. For example, a flat marble surface will reflect most of the sound energy like a mirror whereas a tree trunk covered in textured bark will absorb more of the energy and its irregular shape will scatter the reflections rather than reflecting them in a specific direction.” (Paul White, 2001, report on advanced reverberation)

When a sound hits a surface, it will both be absorbed and reflected. As you can see in the diagram below, some of the sound is transmitted into the material it hits and travels through it, while some travels back the same way it came. This second wave will lose its power or volume because it is split, and will keep reoccurring on other surfaces in the space until it has lost all power to absorption.


The walls of this room are highly absorbant, and at a guess i'd say have an absorbancy co-efficiency of around 95% (95% of a sound wave gets absorbed, 5% reflected), meaning the volume of that sound is halved everytime it hits a wall. This is a HUGE absorbancy level which will make reverb times next to nothing.

If youre interested in more check out RT60, Reverberation, Standing Waves, and Frequency Response.
User avatar #478 to #468 - Welshhobo
Reply +1 123456789123345869
(05/19/2013) [-]
Also, for those interested in how it gets to negative decibels.

Decibels are a relative measurement. If you spoke into a microphone, the recorded volume would be 0dB, because its not relative to anything. If you doubled the volume mechanically, it would be 3dB. If you doubled it again, it would be 6dB and vice versa.

These rooms absorb so much sound that anything spoken gets made 8 times quieter to the speaker. Of course if you spoke directly into someones' ear the room wouldn't make a difference, but if you spoke or made a noise from a position you're stood at, the returned sound would be at least 8 times quieter, which is almost inaudible.
#484 to #478 - backlists
Reply 0 123456789123345869
(05/19/2013) [-]
You forgot to mention the most important thing: which is that decibels are a logarithmic unit. Which is why 6 dB is double the amount of 3dB, not the same increment of difference.
#485 to #484 - backlists
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(05/19/2013) [-]
(oops, I didn't realise you mentioned that in an earlier comment)
#184 - parrotey
Reply +5 123456789123345869
(05/19/2013) [-]
Wait, it's not normal to hear your blood flowing all the time?
User avatar #195 to #184 - memeaholic
Reply +1 123456789123345869
(05/19/2013) [-]
sometimes I hear it when my heart is beating really fast
maybe you have a superpower
User avatar #141 - prettyflyforaderp
Reply +5 123456789123345869
(05/18/2013) [-]
>have kids
> have this room built into my house
>put the in it when they are bad
>while they sit in there I'll come in with ear plugs and then fart and run out
>laugh while their ear drums burst do to my farting
#97 - kmichel
Reply +5 123456789123345869
(05/18/2013) [-]
Without visual stimulation, you also hallucinate. If you stare at yourself in the mirror in a dimly lit room, you will hallucinate and see terrible things within 10 minutes. All the participants who did this in a psychological study experienced these hallucinations.
User avatar #102 to #97 - hueyfreeman
Reply 0 123456789123345869
(05/18/2013) [-]
I'm going to do this, what do you recommend for the "dim" lighting. I was thinking like 1 christmas light hanging from the ceiling?
#107 to #102 - kmichel
Reply 0 123456789123345869
(05/18/2013) [-]
Wow, I got it pretty fast. I'm at a university, and I can access papers free. Try the original publication here: You need to login to view this link but if that doesn't work, go here: mindhacks.com/2010/09/18/the-strange-face-in-the-mirror-illusion/
User avatar #108 to #107 - hueyfreeman
Reply 0 123456789123345869
(05/18/2013) [-]
Results will be delivered at around midnight tonight, I want to wait until it's dark.
#110 to #108 - kmichel
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(05/18/2013) [-]
Good idea. Keep me updated! I hallucinate all the time at night, and don't want to do it in the daytime as well. I suffer from hypnagogic hallucinations.
#104 to #102 - kmichel
Reply 0 123456789123345869
(05/18/2013) [-]
Let me try to find the original research paper, or at least a description of the research. I found it a year ago, and don't have it bookmarked.
User avatar #106 to #104 - hueyfreeman
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(05/18/2013) [-]
Alright, let me know if you do. I was just thinking maybe I'd use a strobelight instead, maybe that would make it worse/better.
#109 to #106 - kmichel
Reply 0 123456789123345869
(05/18/2013) [-]
So apparently you'd need a 25 watt bulb (incandescent), and be about 40 cm (16 inches) from the mirror.
User avatar #112 to #109 - hueyfreeman
Reply 0 123456789123345869
(05/18/2013) [-]
Got it. I've got everything that's needed.
User avatar #122 to #112 - goodguygary
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(05/18/2013) [-]
let me know what the hell you saw when it's over.
User avatar #339 to #122 - hueyfreeman
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(05/19/2013) [-]
You're the only one still here, so here goes. I stood there, dead still, for about 15 minutes (I set a timer) And I really started seeing some ****** up ****. First of all, after a while it looked like there was no light at all even with the dim light behind me. Second, I genuinely couldn't see myself in there. I became a sort of black silhouette with weird grey eyes, and some kind of elderly face. I really wouldn't recommend trying this.

tl;dr I saw an old person with grey eyes staring at me
#385 to #339 - kmichel
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(05/19/2013) [-]
Wow, that's brave of you to try it for that long. Interesting result.
User avatar #114 to #112 - jaevel
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(05/18/2013) [-]
How did it go?
User avatar #162 to #114 - hueyfreeman
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(05/19/2013) [-]
Midnight, bro.
User avatar #91 - shadecrenshaw
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(05/18/2013) [-]
Despite it saying you go mad, it would be really interesting to try, its pretty much a sensory overload as far as I can tell.

I just don't see what's so bad about hearing your own breathing/heartbeat/bloodflow....I guess it would sound gross, but thats about it.
#92 to #91 - intrepidy
Reply +5 123456789123345869
(05/18/2013) [-]
Your brain NEEDS constant stimulation, otherwise it just goes crazy and starts making up crazy stuff.   
   
Much like Cortana in Halo 4, only without the buck teeth.
Your brain NEEDS constant stimulation, otherwise it just goes crazy and starts making up crazy stuff.

Much like Cortana in Halo 4, only without the buck teeth.
#74 - romdadon
Reply +5 123456789123345869
(05/18/2013) [-]
Comment Picture
User avatar #15 - PenguinHearts
Reply +5 123456789123345869
(05/18/2013) [-]
Imagine getting extremely high and then going into this room haha.
#438 - fleszar
Reply +4 123456789123345869
(05/19/2013) [-]
**fleszar rolled a random image posted in comment #317 at good job craig ** 45 min? pffffft I would sleep for 45 hours in there   
   
   
probably unrelated picture
**fleszar rolled a random image posted in comment #317 at good job craig ** 45 min? pffffft I would sleep for 45 hours in there


probably unrelated picture
#447 to #438 - firereadyaim
Reply +2 123456789123345869
(05/19/2013) [-]
i dont know man i usually have trouble sleeping if its too quiet, like when i can hear my own breathing or if my ears are ringing it really bugs me.
User avatar #458 to #438 - vondraco
Reply +2 123456789123345869
(05/19/2013) [-]
Nice roll
User avatar #379 - xXMAQXx
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(05/19/2013) [-]
that room is like my heart
#387 to #379 - oneaboveall
Reply +4 123456789123345869
(05/19/2013) [-]
So dark...   
   
So edgy   
   
You must watch Elfen lied
So dark...

So edgy

You must watch Elfen lied
User avatar #393 to #387 - xXMAQXx
Reply 0 123456789123345869
(05/19/2013) [-]
you know that is one of the more popular ones that i havent gotten to yet...

please if you could, tell me how satisfying it is
#395 to #393 - justanotherzombie
Reply +2 123456789123345869
(05/19/2013) [-]
There is no words to describe the pleasure this show give
There is no words to describe the pleasure this show give
User avatar #327 - solareyes
Reply +4 123456789123345869
(05/19/2013) [-]
Challenge accepted.
User avatar #274 - umaya
Reply +2 123456789123345869
(05/19/2013) [-]
I thought 0 decibels was silence, can someone re-educate me?
#298 to #274 - wyldek
Reply +4 123456789123345869
(05/19/2013) [-]
I'm pretty sure decibels work on a logarithmic scale. Meaning that the greater the magnitude of the negative number, the closer to 0 on an absolute scale.

IE: -20 db = 0.01
#322 to #298 - beefking
Reply +2 123456789123345869
(05/19/2013) [-]
**beefking rolled a random image posted in comment #55 at Signals ** mfw
#237 - psykojet
Reply +4 123456789123345869
(05/19/2013) [-]
But you could sleep so well
User avatar #240 to #237 - strangesir
Reply +4 123456789123345869
(05/19/2013) [-]
How can you, hearing your own body making noises and stuff?
#216 - jacobluke
Reply -7 123456789123345869
(05/19/2013) [-]

my friend's step-sister makes $85/hr on the laptop. She has been laid off for 9 months but last month her pay was $14603 just working on the laptop for a few hours. Read more on this site.... www.daz7.com
User avatar #256 to #216 - defender
Reply 0 123456789123345869
(05/19/2013) [-]
tell that hoe a pimp named slickback wants his goddamn money
#234 to #216 - fruitninja
Reply +2 123456789123345869
(05/19/2013) [-]
GO **** YOURSELF WITH A CACTUS!!!!
User avatar #236 to #216 - huntergriff
Reply +2 123456789123345869
(05/19/2013) [-]
she must be some hardcore porn she's doing to make that much money...
#232 to #216 - MysticTomatoe
Reply +3 123456789123345869
(05/19/2013) [-]
Comment Picture
#228 to #216 - fordun
Reply +4 123456789123345869
(05/19/2013) [-]
Listen ****** i don't give a **** how much money your whore sister makes on the laptop. Go **** yourself and you're sister.
#151 - xgeneration
Reply +1 123456789123345869
(05/19/2013) [-]
**xgeneration rolled a random image posted in comment #2105540 at Friendly **
deaf people are amazing.
User avatar #194 to #151 - mayormilkman
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(05/19/2013) [-]
This is the second of these sort of images I've seen from. Your kink can't escape from us, whoever you are!
#166 to #151 - masterchiefawesome
Reply +4 123456789123345869
(05/19/2013) [-]
is... is that a scientifically impossibly obese harry potter fox bee furry?
is... is that a scientifically impossibly obese harry potter fox bee furry?
#171 to #166 - derpwolf
Reply +1 123456789123345869
(05/19/2013) [-]
Probably.
User avatar #145 - goldfangz
Reply +4 123456789123345869
(05/19/2013) [-]
how is something minus decibels

can you hear better or worse?
does it suck sound out the room?
and what would happen if you put a deaf person in there?
#159 to #145 - bluelips
Reply +3 123456789123345869
(05/19/2013) [-]
it's not about hearing better or worse, you have the sensation every single sound (like your own clothes) is really really loud because your eardrums aren't experiencing everyday noise (there's reeverb everywhere) so they become really sensitive towards even the lightest sound. There are some people who experienced a rain like sound, it is supposed it was the air molecules hitting the eardrum. Pretty amazing stuff can happen in the anecoic chamber.

The walls are made of materials that entrap the sound within them, so they don't have any reeverb at all.

Also you can't just exit the anecoic chamber and simply enter a normal chamber because of the difference of sound between of them. This could lead to the rupture of the eardrum or even death, so there is at least another chamber in the middle, a sort of decompressing chamber.

This type of chamber is mostly used to test accurate loudness of things (for example vacuums before they put them on sale).

Hope I was helpful =)
#168 to #159 - goldfangz
Reply +1 123456789123345869
(05/19/2013) [-]
not really    
   
i didnt know some words: reeverb and anecoic for example    
   
also does that mean negative decibels are louder than positive since you hear everything louder    
   
i never heard my clothes make any for om noise. and how does air bounce of your ears? i can understand the blood flow.    
   
if you fart can you hear the vibrations or the *plop*?
not really

i didnt know some words: reeverb and anecoic for example

also does that mean negative decibels are louder than positive since you hear everything louder

i never heard my clothes make any for om noise. and how does air bounce of your ears? i can understand the blood flow.

if you fart can you hear the vibrations or the *plop*?
#167 to #159 - goldfangz
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has deleted their comment [-]
User avatar #142 - givemecoke
Reply +4 123456789123345869
(05/18/2013) [-]
where can i go to beat that record?
#118 - emcemc
Reply +4 123456789123345869
(05/18/2013) [-]
Let me at the mofo
Let me at the mofo
#99 - mytrakytra
Reply +4 123456789123345869
(05/18/2013) [-]
Sitting in the room.
#20 - anon id: 40675432
Reply 0 123456789123345869
(05/18/2013) [-]
Mfw negative sound.
User avatar #31 to #20 - zgbgydug
Reply +4 123456789123345869
(05/18/2013) [-]
You don't have a face in negative sound?

Anyway, every ten decibels is percieved twice as loud as ten before it. Really -9 is about half as loud as 0, or a quarter as loud as 10.
#140 to #31 - anon id: 09dd3259
Reply 0 123456789123345869
(05/18/2013) [-]
it's actually ten times, not two. so, it's about 10 times quieter than 0 db, and 100 times quieter than 10 db
#296 to #140 - anon id: 20a30eaf
Reply 0 123456789123345869
(05/19/2013) [-]
no, it's twice.
Every increase of 10 dB is perceived as the sound being twice as loud.
#63 to #31 - anon id: fd971f54
Reply 0 123456789123345869
(05/18/2013) [-]
ya its a logarithmic scale, negatives are fractional
#40 to #31 - beggy [OP]
-2 123456789123345869
Comment deleted by beggy [-]
User avatar #79 to #40 - smoothmcgroove
Reply 0 123456789123345869
(05/18/2013) [-]
If a sound is 10db, you won't be able to hear anything below that.

So, if the room is recorded at -9db, you can hear everything.







(...Except for sounds lower than -9db)
User avatar #188 to #79 - treska
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(05/19/2013) [-]
Since the sound power level is:
P=10*log(multiplier) ---> multiplier=10^(P/10), where P is the decibels and log is decimal logarithm. In this case:
multiplier=10^(-9/10)=0.126.
That means that in that room, the sound power level decreases to 12.6% of the original value.
#428 to #188 - anon id: 63ec19bb
Reply 0 123456789123345869
(05/19/2013) [-]
Wow, a smart comment on fj, I thought I would never live to see this day.
User avatar #304 - nonathan
Reply +3 123456789123345869
(05/19/2013) [-]
Wouldn't the room become less quiet with a person in it?