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Has anyone ever been to a museum and found an X on the floor where the auditorium echoes your sound back to that exact spot from every corner?

Whats that called?

I'm having a stoner "how has this not been made public" moment and i want to pretend i'm skilled and enough to build one in my basement.

By the time i finished typing this i realized a pair of headphones and a pedal or two would do the same thing but we're in a natural organic world now and that sounds processed and maybe full of gluten idk.
 

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Not sure what it is called, but I know Science North had a couple of parabolic reflectors set up about 20 metres from each other and with a person standing at the focal point of each one, you could have a conversation in a normal volume voice and no one in between could hear it.

Same principle.
 

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It's a parabolic ceiling, and the X merely indicates the "sweet spot" where all reflections can be heard equally. What's cool is that you can whisper in that spot, and it sounds like you've been mic'd with a high-end Neumann, amplified, and fed to high-end headphones.

I don't know if it's still there, but the Place Victoria Metro stop in Montreal had one of those, years back. Sometimes you'd see some homeless person wandering through, and when they passed the magic X-spot and could hear all their reflected mumblings in super hi-def, they'd get this startled look on their face of "I may hear voices, but I'm not THAT fricking nuts. WHAT is going on here?"

Parabolic_Reflector
 

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Is it an anechoic chamber?
Nope - that's the opposite - no echo at all (you'd be surprised how much echo there is in any given room you're in - just not always the obvious slapback we associate with an 'echo' but much shorter delay).

I'm not even sure there is a word for what the OP describes, but I know what he means. I suggest googling that echo art installation at Pearson airport and see what they call it. ... ah mhammer FTW.
 

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Is it an anechoic chamber?
I was just in one of those a few weeks back, at the Museum of Science and Technology.
Anechoic (no echoes) chambers are used when the sound pressure level of something needs to be measured, or otherwise highly controlled. They are generally heavily soundproofed from the outside world as well. For instance, when speaker efficiency is measured, the speaker is placed in an anechoic chamber, provided with a standardized signal, and measured with a calibrated mic from a standardized distance. The reason for doing this is to make sure that all sound detected is coming ONLY from the speaker and not from any other sources, whether reflected or from outside the room itself. Neurophysiological and audiology researchers also use them. When I was at U.Vic. the neuropsychology folks had one.

The godfather of this stuff is Dr. Floyd E. Toole, a New Brunswick native (has an engineering building named after him at UNB if memory serves), who worked at the National Research Council for many years and is still a highly in-demand consultant on acoustics. Here's one of his many works:
https://www.amazon.ca/Sound-Reproduction-Acoustics-Psychoacoustics-Loudspeakers/dp/0240520092
 

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Not sure what it is called, but I know Science North had a couple of parabolic reflectors set up about 20 metres from each other and with a person standing at the focal point of each one, you could have a conversation in a normal volume voice and no one in between could hear it.

Same principle.
My house is like this. I talk but no one hears it. Not the wife, kids... no one. Ever.
 

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Not sure what it is called, but I know Science North had a couple of parabolic reflectors set up about 20 metres from each other and with a person standing at the focal point of each one, you could have a conversation in a normal volume voice and no one in between could hear it.

Same principle.
That's why they used to use such reflectors for mic'ing up football and other referees from the sidelines. You point the mic and surrounding reflector at the official, and when they talk, they are the loudest thing being picked up. Of course, that was before the wireless mics that refs use on the field nowadays.
 

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Telecom, as well. With a parabolic dish at each end, a receiver can 'hear' a 1 watt transmitter from 30 or 40 miles away (each dish adds about 30 dB of gain, compensating for the path losses).


That's like the joke....

My wife said to me "You didn't hear a word I was saying" and I thought, that's an odd way to start a conversation.
I thought the correct response to this was "Medium rare, please. And I'd like sour cream and chives with the potato as well, thanks for asking."
 

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All you need is a pool! If I go for a late night dip (weather permitting of course) my in-laws across the road can hear EVERYTHING!

...apparently.
 
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