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High-quality OLED displays now enabling integrated thin and multichannel audio

sciencedaily.com

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Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#11
post #9
post #6

This is impressive. Though perhaps not very useful. Humans (and animals in general) are quite bad at precisely locating sound anyway. We only have two input channels, the right and the left ear, and any location information comes from a signal difference (loudness usually) between the two.

Localization of sound is primarily based on the time difference between the ears. Localization is also pretty precise, to within a few degrees under good conditions.

Nit: time difference, phase difference, amplitude difference, and head related transfer function (HRTF) all are involved. Different methods for different frequency localisation.

There's this excellent (German?) for website that lets you play around and understand these via demos. I’ll see if I can find it.

Edit: found it, it’s https://www.audiocheck.net/audiotests_stereophonicsound.php

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#13
post #9
post #6

This is impressive. Though perhaps not very useful. Humans (and animals in general) are quite bad at precisely locating sound anyway. We only have two input channels, the right and the left ear, and any location information comes from a signal difference (loudness usually) between the two.

Localization of sound is primarily based on the time difference between the ears. Localization is also pretty precise, to within a few degrees under good conditions.

I think for stereo sound, media like music, TV, movies and video games use loudness difference instead of time difference to indicate location.

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#14

This is a long shot but anyone know if there's an audio recording of the sound the display produced? Curious Edit: Found it: https://advanced.onlinelibrary.wiley.com/doi/10.1002/advs.20... Go to supporting information on that page and open up the mp4 files

Good find - the first video is a frequency sweep, video 2 has some music.

Edit - I'm not sure that's the same thing? The release talks about pixel based sound, the linked paper is about sticking an array of piezoelectric speakers to the back of a display.

edit 2- You're right, the press release is pretty poor at explaining this though. It is not the pixels emitting the sound. It's an array of something like 25 speakers arranged like pixels.

https://www.eurekalert.org/news-releases/1084704

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#15
post #6

This is impressive. Though perhaps not very useful. Humans (and animals in general) are quite bad at precisely locating sound anyway. We only have two input channels, the right and the left ear, and any location information comes from a signal difference (loudness usually) between the two.

The main utility isn't for the user to more precisely locate the sound source within the screen. Phased speaker arrays allow emitting sound in controlled directions, even multiple sound channels to different directions at the same time.

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#16
post #13
post #9

Earlier quoted context omitted.

Localization of sound is primarily based on the time difference between the ears. Localization is also pretty precise, to within a few degrees under good conditions.

I think for stereo sound, media like music, TV, movies and video games use loudness difference instead of time difference to indicate location.

At least video games use way more complex models for that, AFAIK. It might be tricky to apply to mixes of recorded media, so loudness is commonly used there.

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#17
Many TFT and OLED panels today can produce sound unintentionally based on screen contents. This is mostly noticeable with repeating horizontal lines, which tend to produce whining at some fraction of the line frequency. Likely electrostiction.

This here seems to be about adding separate piezoelectric actuators to the display though, it doesn’t seem to use the panel itself.

> by embedding ultra-thin piezoelectric exciters within the OLED display frame. These piezo exciters, arranged similarly to pixels, convert electrical signals into sound vibrations without occupying external space.

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#19
post #12

That’s super impressive. I guess that would work for a notification speaker. But for full sound I have doubts about the low frequencies. I would assume you would need a woofer anyway in a home setting.

These are a thing: https://hackaday.com/2019/10/26/building-the-worlds-best-dml...

Re: High-quality OLED displays now enabling integrated thin and multichannel audio

#20
post #4

> This breakthrough enables each pixel of an OLED display to simultaneously emit different sounds > The display delivers high-quality audio Are multiple pixels somehow combined to reproduce low frequencies?

Theoretically, any frequency can be produced by the interference of ultrasonic waves, but the amplitude is questionable, given that these emitters are embedded into a thin substrate.
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