世界上最安靜地方 吸音率九成九
作者： 莊瑞萌 | 台灣醒報 – 2012年7月12日 下午3:41
【台灣醒報記者莊瑞萌綜合報導】在這裡，你什麼都聽不到！美國明尼蘇達一處實驗室打造了全世界最安靜的房間，房間由90公分厚的玻璃纖維與隔音牆打造，吸音率接近百分百，幾乎完全隔絕外界聲音，已被金氏世界紀錄正式列為全球最安靜房間。不過，人類能待在屋內最長的時間為45分鐘，否則就會出現噁心或幻聽等副作用。
由歐爾菲德實驗室設計的「暗房」，其吸音率高達99.9％，由於已接近完全無聲音境界，人類在屋內會出現感官特別敏感，包括自己體內任何律動都聽得到。一般人能待在屋內極限是45分鐘，主要是人類走動時，有時候須靠著聲音辨別方向感，因此待在太安靜的地方，可能會因失去方向感，出現幽閉恐懼症、噁心、恐慌與幻聽等症狀，最好的方式是坐在地上。
實驗室創辦人歐爾菲德表示，「當四周寂靜無聲，你的耳朵就會開始適應，會聽到越多聲音，待在「暗房」時，除了會聽見自己心跳聲，有時候會聽得到肺部與胃部發出的聲音，到最後你會發現自己就是聲音。」
在「暗房」內待過45分鐘的美國小說家佛依（George Foy）曾投書英國《衛報》表示，「大約兩分鐘後，我開始聽到自己呼吸，於是我刻意屏住呼吸，但卻又聽見自己心跳，甚至還聽到血液在血管內流動的聲音，等到我聽到自己頭骨上的頭皮移動所發出的聲音，莫名感覺湧上心頭，那種聲音彷彿就像金屬互刮發出的聲音。」
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90cm厚的wedge
我猜那CUT-OFF FREQUENCY應該不會只是低於80Hz
結構裡面應該另有玄機
CUT-OFF FREQUENCY應該會低於50Hz
BACKGROUND NOISE-9.4dBA==>台灣何時才能建一間???
其實只要是無響室
20dBA的環境就已經會讓人開始聽到自己的心跳感受到血液流動並有噁心感了
http://minnesota.publicradio.org/display/web/2012/04/03/daily-circuit-quiet-room/
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90cm厚的wedge
我猜那CUT-OFF FREQUENCY應該不會只是低於80Hz
結構裡面應該另有玄機
CUT-OFF FREQUENCY應該會低於50Hz
BACKGROUND NOISE-9.4dBA==>台灣何時才能建一間???
其實只要是無響室
20dBA的環境就已經會讓人開始聽到自己的心跳感受到血液流動並有噁心感了
In Minneapolis, the world's quietest room
10:50 AM, April 3, 2012
10:45 AM, June 21, 2012
Steven Orfield, president of Orfield Laboratories, stands in the anechoic chamber in Minneapolis that's been dubbed by Guinness as being the world's quietest room. (MPR Photo/Tom Weber)
AUDIO
- In Minneapolis, the world's quietest room(program audio)
This morning, we're talking about noise pollution and the negative health affects it can cause. In Minneapolis' Seward neighborhood, you can find the world's quietest room.
The room, which holds the Guinness World Record designation, is located in the Orfield Laboratories. The recording studios where "Funkytown" and Bob Dylan's "Blood on the Tracks" were recorded are also in this building.
The world's quietest room is called an anechoic chamber, which means there is no echo as it absorbs sound. Sound doesn't bounce off the walls the way it does in a regular room.
A typical quiet room you sleep in at night measures about 30 decibels. A normal conversation is about 60 decibels. This room has been measured at -9 decibels.
Orfield Labs uses the room to test products, including switches that go on car dashboards and the sound an LED display makes on a cell phone to make sure they're not too loud.
To get into the anechoic chamber, you go through two bank vault-like doors. The floor in the room is mesh like a trampoline so there's nothing on the floor for the sound to bounce off of. The walls are lined with sound-proofing wedges that are a meter long so they absorb the sound.
"When you sit in any rooms a person normally sits in, you hear the sound and all its reflections," said Steven Orfield, president of Orfield Labs. "When you go into an anechoic chamber, there are zero reflections. So if you listen to me talk and hear my voice, you're hearing my voice exactly. And if I turn around and talk, the only thing you'll hear is the sound bending around my head."
