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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

#41

Post by kragen »

atoav wrote: post #35

So you are saying we get dieplays that could run wavefield synthesis? If you don't know what wavefield synthesis is: you basically have an array of evenly spaced speakers and for each virtual sound source you drive each individual speaker with a specially delayed signal that recreates the wavefield a sound source would create if it occupied that space. This is basically as close as you can get to the thing being in a…

Because audio runs at such low sample rates, it's not exorbitant by current standards. Suppose you have an 8×16 array of speakers behind your screen, each running at 96ksps. That's only 12.3 million samples per second to generate, on the order of 200 million multiply-accumulates per second for even the most extreme scenarios. Lattice's iCE40UP5K FPGA https://www.farnell.com/datasheets/3215488.pdf#page=10 contains 8 "sysDSP" blocks which can do two 8-bit multiply-accumulates per clock cycle at 50MHz even when pipelining is disabled, so 800 million per second. It's 2.1 by 2.5 mm and costs US$5 at Digi-Key. I'm not familiar with AVX, but I believe your four-core 2GHz AVX512 CPU can do 256 8-bit multiply-accumulates per cycle, five hundred thousand million per second, so we're talking about an exorbitant amount of computation that's 0.04% of your CPU.

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

#42

Post by miguelnegrao »

badmintonbaseba wrote: post #39
miguelnegrao wrote: post #30

Earlier quoted context omitted.

Unreal Engine, the only engine I'm more familiar with, implements VBAP which is just amplitude panning when played through loudspeakers for panning of 3D moving sources. It also allows Ambisonics recordings for ambient sound which is then decoded into 7.1. For headphone based spatialization (binaral synthesis) usually virtual Ambisonics fed into HRTF convolution is used, which is not amplitude based, specially height…

Which makes sense, there is only so much you can do with loudspeakers to affect the perceived location, you don't really know where the loudspeakers and the listener are located relative to each other.

Actually, the farther way the speakers are from the angles specified in the 7.1 format (see https://www.dolby.com/about/support/guide/speaker-setup-guid...) worse will be the localization accuracy. And if the the person is not sitting centered relative to the loudspeakers, but closer to one of the loudspeakers localization can completely collapse, and it will sound like the sound only comes from the closest loudspeaker.

In the case of gamers, they are usually centered relative to the loudspeakers, and usually the loudspeakers tend to be placed symmetrical to the computer screen, so the problem is not so bad.

For cinema viewers sitting in the cinema the problem is much worse, most of the audience is off center... That is why 7.1 has a center loudspeakers, the dialogue is sent directly there to make sure that at least the dialogue comes the right direction.

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

#43

Post by miguelnegrao »

dedicate wrote: post #2

My mind immediately goes to VR – imagine how much more immersive that would be!

For VR, since you have to put the helmet in your head, it is usually assumed users don't mind putting headphones as well, so most solutions are via headphone-based spatialization.

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

#44

Post by 1970-01-01 »

steelbrain wrote: post #10

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

This technology literally sounds like a terrible idea. Why do I want to hear one drummer's drum over the others?

https://advanced.onlinelibrary.wiley.com/action/downloadSupp...

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

#45

Post by PaulHoule »

K0balt wrote: post #36
cubefox wrote: 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.

You are misinformed. Amplitude, spectral, and timing are all integrated into a positional / distance probability mapping. Humans can estimate the vector of a sound by about 2 degrees horizontal and 4 degrees vertical. Distance is also pretty accurate, especially in a room where direct and reflected sounds will arrive at different times, creating interference patterns. The brain processes audio in a way not too dissim…

I learned to move around in dark rooms when I was young, I definitely can "feel large objects by the void they make" and people often turn on the lights because they thing I need them to "see" when I really don't.

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

#48

Post by skhameneh »

lmpdev wrote: post #5

Would the vibration be detectable via touch? It would be wild to integrate this into haptics

Audi somewhat did this with the display in the Q8 E-Tron. I don’t recall if the display is OLED, but it has excellent haptics.

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

#49

Post by amelius »

pornel wrote: post #47
amelius wrote: post #46

How can this produce directional sound beams if there is a glass plate covering the display?

Probably similar to antennas — using phase shifting and interference.

Yes, probably, but my question was more about the glass cover and if it wouldn't basically destroy the effect?

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

#50

Post by layer8 »

The talk about pixels is misleading. The research paper doesn't mention pixels. They attached a 3x3 array of piezoelectric elements (roughly 3 cm in diameter each) behind a 13" OLED panel (one picture also shows a 5x4 array), using a sturdy frame structure to minimize interference of acoustic vibrations between the 9 (or 20) elements of the array.

Not to say that this isn't interesting, but it’s not display pixels emitting sound.

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