Thanks :-)
"The anechoic (meaning echo-free) chamber at Orfield Labs in Minnesota absorbs 99.99% of sound, making it the quietest place in the world, according to the Guinness Book of World Records."
"While a human can normally hear sounds as low as zero decibels (an average conversation runs at about 30 decibels), the background noise in the anechoic chamber has been measured at -9.4 decibels."
"Companies use the chamber to test the sound levels of products, such as washing machines, refrigerators and Harley Davidson motorcycles. NASA uses a similar chamber to perform stress tests on astronauts."
Still baffled as to why the beeb IP restrict this. I can acknowledge it's part of BBC Worldwide, and therefore not covered in the licence fee, but what harm it would do to let Britain have the same access as the rest of the non licence paying world is beyond me.
tl;dr is that there exists a chamber so quiet that people find it extremely uncomfortable (for various reasons, feel free to speculate), at Orfield Labs. It works simply by reducing echo (anechoic chamber). There will be an award for anyone standing in there for more than 45 minutes. And it's in Guinness Book of Records as the most quiet place on earth.
What is the deal with BBC.com anyway?
The message we get when visiting this URL:
"We're sorry but this site is not accessible from the UK as it is part of our international service and is not funded by the licence fee. It is run commercially by BBC Worldwide, a wholly-owned subsidiary of the BBC, the profits made from it go back to BBC programme-makers to help fund great new BBC programmes. You can find out more about BBC Worldwide and its digital activities at www.bbcworldwide.com.
"If you are looking for travel news in the UK, please visit the Travel News site."
[0]: http://en.wikipedia.org/wiki/Television_licensing_in_the_Uni...
https://news.ycombinator.com/item?id=3798283 The World's Quietest Room: Nobody Has Lasted More Than 45 Minutes In It (dailymail.co.uk)
https://news.ycombinator.com/item?id=3781040 The Quietest Room in the World (tcbmag.com)
https://news.ycombinator.com/item?id=3783478 The quietest room in the world (tcbmag.com)
https://news.ycombinator.com/item?id=3802268 Quietest place on earth messes with the head. (yahoo.com)
https://news.ycombinator.com/item?id=3821238 The quietest place on earth (neatorama.com)
https://news.ycombinator.com/item?id=4053296 A room so quiet, no one can spend more than 45 minutes in it (timesherald.com)
https://news.ycombinator.com/item?id=4219266 This Is The Quietest Place On Earth (bitrebels.com)
https://news.ycombinator.com/item?id=4565325 World’s Quietest Place Lets You Hear Your Internal Organs (odditycentral.com)
Your suspicion was correct. And it might just be technically wrong anyway as salford states its anechoic chamber is even quieter.
Is there any way I can volunteer for an attempt?
"Group tours of the labs are available a few times a year and include a brief stop at the anechoic chamber (call the lab for details). But the facility has had so much interest in the 45-minute challenge that the founder Steven Orfield is considering making that option available to the public within the next year, and is working with the Guinness Book of World Records to establish an official record for the longest time spent in an anechoic chamber."
(Thanks for the quote. I'm in the UK and the page is, frustratingly, blocked to us.)
Taken from Master Handbook of Acoustics 5th edition (page 39-40): The human ear cannot detect sounds softer than the motion of air particles on the eardrum. This is the threshold of hearing. There would be no reason to have ears more sensitive, because any lower-level sound would be drowned by the air-particle noise. This means that the ultimate sensitivity of our hearing just matches the softest sounds possible in an air medium.
erm, decibel what exactly? Decibel is a ratio between two values. If you don't state the one compared with, you're talking pretty much nonsense.
http://en.wikipedia.org/wiki/Decibel
Possible units (dropped by the article):
dB SPL
dB SIL
dB SWL
dB(A), dB(B), and dB(C)
dB HL
dB HLI would think any half decent noise chamber would do the job.
"All men's miseries derive from not being able to sit in a
quiet room alone."
- Blaise PascalI have spent time in Anechoic chambers for doing noise level and vibration testing on equipment. They are disconcerting for sure, but I have to imagine someone who never hears anything would not be disoriented.
The shape of the walls messes with me I think more than the sound. We aren't used to not having flat surfaces to judge distance against and not having anything that is only "one" distance away definitely works the part of the brain that does depth perception.
>$300-$400/hour
That doesn't sound too bad actually, I expected an order of magnitude more.