
Acoustic Location and Sound Mirrors (2004) - spking
http://www.douglas-self.com/MUSEUM/COMMS/ear/ear.htm
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samcheng
The modern version of this utilizes an array or grid of microphones with
synchronized clocks, and is quite effective in locating gunfire.

The most famous manufacturer is "ShotSpotter."

[https://en.wikipedia.org/wiki/Gunfire_locator](https://en.wikipedia.org/wiki/Gunfire_locator)

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jcims
‘Acoustic camera’ seems to be the marketing term used for such products.
Searching for this on YouTube will yield all manner of examples. The size of
the device will dictate range and frequency response, there’s a neat study of
elephants with one here:
[https://youtu.be/Xl7LnAob2T8](https://youtu.be/Xl7LnAob2T8)

One thing that I think is interesting is that you could record a setting with
one of these contraptions (eg party, train station) and go back later to do
beamforming in software to zero in on specific conversations.

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sgt101
Using these to find aircraft was pretty marginal, but when applied to finding
artillery or snipers sound location can be very effective and very accurate.
It was used extensively in the later stages of WW1 to deliver counterfire.

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djaychela
It's bizarre looking at the technology used, but I guess at the time
mechanical technology seen here was the only way to do this at the right price
(or possibly any price - I'd imagine that electronic performance simply wasn't
good enough at the time in terms of noise floor and sensitivity?).

Looking at most of these though, I wonder how many operators went deaf because
of a loud sound being captured by them? I've been recording music
professionally for the last 25 years, and seeing things like this makes me
wince!

