[HN Gopher] A technique that enables people to hear ultrasonic s...
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A technique that enables people to hear ultrasonic sources above
20kHz
Author : giuliomagnifico
Score : 58 points
Date : 2021-06-08 07:02 UTC (1 days ago)
(HTM) web link (www.aalto.fi)
(TXT) w3m dump (www.aalto.fi)
| jakubp wrote:
| Clickbait :( It's a device that plays back - through headphones -
| specific normal-range sound which is crafted in such as way as to
| help you locate a source of another (ultra)sound which you
| normally wouldn't hear. Nothing in this thing enables people to
| hear ultrasonic sources. They still hear sound from normal range.
| gpcr1949 wrote:
| I agree, and real time pitch shifting (as is done with the bat
| sounds in this work) is itself a non-trivial procedure where
| certain weigh-offs have to be made, so even pitched shifted it
| is not an accurate (or even easily invertible) representation
| that you can mentally pitch up. (this is not a problem for non-
| realtime pitch shifting where you would adjust the tempo
| accordingly).
| dahart wrote:
| I wonder if you could hear bats directly by having a headset /
| amplifier that contacts your skull rather than putting a speaker
| over your ear. It's been reported that humans can hear ultrasonic
| frequencies via bone contact. (I'd speculate identifying the
| source direction doesn't work though.)
| https://en.wikipedia.org/wiki/Ultrasonic_hearing
| Enginerrrd wrote:
| I can hear bats normally. I have a freakishly large hearing
| range.
| exabrial wrote:
| Up until about 26, I could hear well up to 23khz. Nowadays it's
| limited to about 16k, and I have a deaf spot around 14khz
| cameronh90 wrote:
| I'm still hearing up to 19kHz at 31.
|
| Frankly, it just allows me to hear more high pitched squeals
| and "animal repellent" devices. My ability to interpret normal
| sounds and speech seems average.
| tantalor wrote:
| The paper explains why basic pitch shifting in hearing aids is
| not localisable,
|
| > A less drastic version of such processing is utilised by
| certain hearing aids, where high frequencies that are audible to
| normal-hearing subjects, but inaudible to those who are hearing-
| impaired, are shifted down to the audible range of the wearer.
| However, such an approach is problematic in terms of the
| preservation of directional cues, since the acoustic filtering
| effects due to the diffraction caused by the head and pinna vary
| substantially with frequency. Therefore, the directional cues
| delivered by the pitch-shifted signals do not carry the
| appropriate information related to the source direction that a
| human subject would have evolved and grown accustomed to.
|
| https://www.nature.com/articles/s41598-021-90829-9
| jcims wrote:
| I wonder if this would apply to mixing in a frequency that
| would result in an audible heterodyne mix (think like active
| noice cancelling but using a waveform that is designed to
| downconvert vs cancel).
|
| I do believe there is a method to use this to give blind folks
| an ambient doppler tone from objects in their vicininity. I
| just don't have the chops or time to try it out.
| evo wrote:
| I wonder if you could build some sort of deliberate reflector
| into a microphone housing to generate comb filtering that an
| analytic technique (or ML) could derive spatial data from. I
| know in the limit this is possible, since there's dummies used
| for binaural recording or testing earbuds, but could an
| intentionally designed mechanism accomplish the same thing in a
| smaller package?
|
| It'd be neat if you could then encode the spatial information
| and use an HRTF on the destination receiver to appropriately
| place the sound in the listener's soundstage.
| hinkley wrote:
| I know someone missing a lot of the high end, and he has really
| enjoyed the pandemic because all of his social interactions are
| online, where everyone is wearing headphones, and everyone is
| suffering from the same handicap:
|
| No conferencing software that I'm aware of has solved the
| cocktail party effect. Since nobody can triangulate sounds
| properly, nobody can filter out side conversations or external
| noises. Everyone has to take turns to be understood, and if
| they don't, the guy with hearing aids doesn't get singled out
| by having to bring it up.
| TaylorAlexander wrote:
| It can be done with a normal PC but I loved meeting people in
| a VR environment where you could walk around and form groups
| and you only heard audio from nearby people. They also had a
| movie theater with a movie everyone could watch at the same
| time.
|
| But any interface where you can move a character in a world
| would be enough to make this work. It's lovely because you
| can drop in and listen to a convo and walk away to another if
| you'd like.
| meatmanek wrote:
| For a hackathon last year, I patched Jitsi to play each
| person's audio from a different angle using the web audio
| spatialization APIs[1], and it really does help the cocktail
| party effect tremendously- people laughing or talking over
| each other (extremely common in physical conversations) don't
| make it impossible to understand the other person like when
| everything is mixed to a mono channel as it is with most
| video conferencing software.
|
| 1. https://developer.mozilla.org/en-
| US/docs/Web/API/Web_Audio_A...
| OJFord wrote:
| That's an awesome idea & project, but mightn't it feel
| jarringly like being surrounded by people talking at you?
|
| I think I'd at least want them all in the, say, central
| 160deg in front of me. At which point I wonder how good the
| 'spatialisation' is, how many people could be meaningfully
| supported.
|
| Because you can't just have alternate speakers spaced out
| for maximal distinction - the same speaker suddenly coming
| from somewhere else would be even more jarring.
|
| Really cool though.
| mackmgg wrote:
| Apple just announced this as a feature for FaceTime at WWDC
| (though not out until the fall, which seems poorly timed).
| I've wondered for the past year why no major conferencing
| software has implemented that.
| hobs wrote:
| Mumble does have positional audio but it has to have a
| game/input source that supports reporting the position of the
| player - always wanted to test it one day.
| Groxx wrote:
| Pretty much all the VR ones do this, as you have a spacial
| representation to work from, from what I've seen. And there
| have been some recent-ish things like https://gather.town/
| that should be capable as well, though I'm not sure if they
| do. But yeah, Zoom doesn't.
| thih9 wrote:
| I'd love to hear an audio example that demonstrates this
| effect.
| whalesalad wrote:
| I wish I could do the opposite and turn my hearing down or
| eliminate certain frequencies altogether.
| OJFord wrote:
| Ha, would be.. fun? interesting? something? to have an app or
| little device that's sort of an 'equaliser for your ears'.
|
| Presumably there's nothing technical stopping that for those
| with hearing aids fitted? Just insufficient use case / desire
| for such granular control. I'd be surprised if you can't get
| them with something more dumbed down like a 'quieten crowds' or
| 'loudness' switch.
| yread wrote:
| Step 1: lose sight?
|
| There might be blind people who orient themselves by echolocation
| - maybe not ultrasonic but still pretty cool
|
| https://www.discovermagazine.com/mind/the-blind-individuals-...
| [deleted]
| ushakov wrote:
| aalto never ceases to amaze
| macawfish wrote:
| I desperately want to wear one of those things on my head with
| the little turquoise ball sticking out of it
| anyfoo wrote:
| "Humans can observe what and where something happens around them
| with their hearing, as long as sound frequencies lie between 20
| Hz and 20 000 Hz."
|
| I wish. This might be true if you are very young, but
| deteriorates rather fast.
|
| In a related vein, I was curious whether this would be something
| miraculous that made humans hear the actual frequencies over
| 20kHz somehow, but it's of course the much more likely
| interpretation: High frequencies are aliased down into lower
| frequencies where you can then hear them normally.
|
| Still seems to have cool applications, and if I understand
| correctly, it's going through great length to make the sounds
| still intuitively localizable, which must make for a neat
| experience.
| giuliomagnifico wrote:
| Yes it's more "identify" rather then "hear", but could be
| useful for various applications.
| Jeff_Brown wrote:
| The headline should mention the spatialization. Otherwise this is
| just pitch-shift, which we've had for years already.
| [deleted]
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(page generated 2021-06-09 23:01 UTC)