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This is often used by audio mixing engineers and taught in a roundabout way at schools and studios. We think a lot about where thins “sit” in the mix. Proximity wise, and even height wise in a stereo mix. Eventually you learn how to locate things in headphones and it’s a really weird sensation when you realize you can do it. The kicker is we start out by simulating real environments in mixes, but then end up having to simulate what people expect from the medium as opposed to real life. For example something I learned doing video audio, if someone is writing something on a train, viewers expect to hear the pen on paper. But irl, there’s not a chance it’s audible. Explosions are always distorted because microphones end up clipping due to the volume, etc.

A great book on spatial simulation is The Art of Mixing by David Gibson. Older but forever relevant

relevant video: https://www.youtube.com/watch?v=PD3Y1l8XyUw

It appears that the hardest part of echolocation for humans is the "produce a directed, crisp click" part. The "process the sound" part is readily handled by our brains with a relatively mild learning curve.

I noticed when I was younger that I can "hear" when I'm near a wall, or just generally get a sense of the size of space I'm in solely via sound, but it never occurred to me to make a "ping" to sense the resulting sound reflections! Super interesting - I will have to try this. Probably my prior spatial sense from hearing was based on really subtle background noise of either my own footsteps or just environmental sounds reflecting around, I guess? I always felt like I am "hearing the room I'm in" but never quite knew how else to describe the sensation, but knowing people quite literally make a clicking noise to echolocate suddenly makes it much more clear!

There is a wonderful book about the blind man who was probably one of the earliest innovators in using a cane for echolocation. "A Sense of the World" by Jason Roberts is the story of James Holman, who traveled the world in the early 19th century despite being blind, often being in a great deal of pain, and having limited mobility.

Here's an idea, use a (portable) ultrasound emitter device that sends a pulse every set second and use an earpiece receiver that produces equivalent acoustics in audible range. The setup may reduce "tongue-fatigue' and the ultrasound will travel farther and can reflect off smaller objects. Would be an interesting experiment if nothing else.

I don't have much sense of the reasonably expected or maximium performance of this ability. They give a few sensational demonstrations, but how accurate is it (as in complete, correct, and consistent)? How fast? In what environments? How granular? Is it practical for everyday use?

For some interesting context, here is a description of dolphin echolocation:

https://www.britannica.com/animal/cetacean/

"The amount of information obtained by an echolocating dolphin is similar to that obtained with the eyes of a sighted human. ...

Toothed whales use extremely high frequencies, on the order of 150 kilohertz, for refining spatial resolution from their echoes. They are capable of “seeing” into and through most soft objects such as other dolphins, though the effectiveness of toothed whale echolocation drops off at distances greater than about 100 metres."

Maybe with enough practice ...

A few years ago, I was a frequent visitor to a public swimming pool, same day, same time. Apparently with similar swimming habits, there was an elderly person who was humming all the time. In the pool, in the shower, in the lobby, rather loud but not too much. I initially attributed it to elderly quirkiness. It was only after several encounters that I realized he was blind. The point is, I only figured that out when I saw him with a white cane outside, not at all by the way he moved inside or used the objects - he was navigating the space just like anyone else, and it was a rather crowded place. That was the day I learned that echolocation in humans is a thing.

Related:

- Humans Can Learn to Echolocate (Livescience, 2015) https://news.ycombinator.com/item?id=10699105

- How humans echolocate 'like bats' (BBC, 2018) https://news.ycombinator.com/item?id=16782557

- Humans Can Learn How to 'Echolocate' in 10 Weeks, Experiment Shows (Sciencealert, 2021) https://news.ycombinator.com/item?id=27404132

- Teach yourself to echolocate - 106 comments https://news.ycombinator.com/item?id=18208334

E- chocolate

E- chocolate

Don’t get it.

Oh..!

Meanwhile, after reading this article, I have my face one inch from a wall making clicks to see if I can hear the echo. Hopefully, nobody sees, or hears, me.

I’m wondering if we use it more than we think. When I have my headphones in with noise cancelling on I’m more inclined to bump something in my house I normally wouldn’t or misjudge a distance etc. Pretty crazy to think about forming a subconscious, audio-based world

This is really interesting. As someone who's been gradually losing his vision, I've noticed some of this stuff on my own, but it's nice to see a good writeup so one doesn't have to figure out everything from first principles.

Just one more thing to add to my bag of tricks.

it's somewhere between silly and mischievous that AtlasObscura provides cute visual drawings yet fails to provide acoustic examples.

I'm curious if people with aphantasia would also be able to create a "mind map" of the area around them

I have tinnitus and can't hear much in a range around 4.5khz... I wonder if this would still work for me

Teach yourself to echocolate

(2018)

I initially misread it as “Treat yourself to a chocolate”

Maybe only distantly related to this, but thought it worth sharing that when I visited Seattle for the first time this year I caught a show by a band called La Cerca at Central Saloon and loved their song “Echolocation”, with ethereal sounding guitars, including the bass: https://www.youtube.com/watch?v=1NYeqA2Kve8

I'm so glad this is surfacing. I remember reading about the skepticism scientists had about this only for them to be finally proven wrong.

My anecdotal experience is that we are so out of touch with our bodies these days that we routinely underestimate just how adaptable we truly are if we have the will or need to learn. So I get frustrated when very useful things like echolocation are suppressed by ignorant and cynical scientists who are unaware of their blind sides because they think they studied hard and read a bunch of papers.

Our realities are shaped by our own experiences but what is sad is when people then shape other people's realities based on their own skewed realities.

I'm glad that the internet is so good at spreading disparate, niche and folky knowledge and forcing scientists to reconsider their priors more often.