The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Future cinema LED screens
Old 1 week ago
  #1
Lives for gear
 

Thread Starter
Future cinema LED screens

The picture folks including installers I spoke to sees the future using LED screens instead of actual screens and projection (including projector maker Christie).
A LED screen will give higher quality picture and a blacker black yada yada yada.

But IF the future is LED screens in cinemas. Then the speakers have to be placed above the screen and not behind it.

What are your thoughts regarding this type of setup?
The main drawback is obviously that the sound won’t appear to be centred at the Center of the screen in height. I have only been to one cinema where they did this and I found it a bit weird. It was hard to say if it was the very different sounding speakers or the placement that was the biggest issue there.

Do you think they are correct? Will projection and screens change sooner rather Than later (5-10 years)?
Old 1 week ago
  #2
Lives for gear
 

Quote:
Originally Posted by ErikG View Post
A LED screen will give higher quality picture and a blacker black yada yada yada.
Sounds like you haven't been to a Dolby Cinema yet. It offers 1million:1 contrast ratio with projection (dual Laser)
Old 1 week ago
  #3
Lives for gear
 

Thread Starter
No not yet, several others in the talks I had have though. And even compared to Dolby cinema they said it’s the only real way to improve picture quality.

Why would that be?

Below are their comments not mine:
Basically to get great picture we need to get rid of the perforated screens as they create moarè, it gets worse at higher resolutions.

Woven screens are an option but no One has been able to build larger than 4m high, and stitching them together is not good for picture quality as the seems are visible. It is also impossible to get the best possible sharpness with a woven screen as each strand will be at a different focus plane. To me the difference has to be minuscule but technically true.
Also to get proper tension in a woven screen over 20m is very difficult next to impossible (the reason why sailboat sails no longer are made in woven Dacron for racing (my comment)).

And I think we can all agree that while a perforated screen is not optimal for picture it doesn’t do sound any favours either with HF reflexes causing Additional distortion and the screen itself severely filters the sound so it has to be compensated with EQ.

So while I personally do not wish for this to happen the question is, will it? And how much does it impact the sound?

Last edited by ErikG; 1 week ago at 09:56 AM.. Reason: Adding stuff and clarifying things.
Old 1 week ago
  #4
Here for the gear
I would ask myself more whether it is a big deal. In terms of image quality todays laser projection and coated screens are a big improvement over what we had a few years ago (especially the black levels they are talking about.)
Unless it was a cheap cinema, I never had any issues with sound either as a consumer. Even if you have to compensate the front channels with a bit of EQ.
I personally think that not being able to have holes is much more of an issue with LED screens than not. Bass is pretty pumpy and close to the screen. Not sure how well LED wiring will hold up for longer periods of time when you need the small holes to properly flow the air through.
Even on my consumer 5.1 set I had to move the speakers from the top of the wall to in the middle because it just doesn't sound right.

Also a second reason of LED being a bad idea is costs. In an ideal world you don't want to multiple square LED panels as in a cinema, where people are pretty close, will see the edges without LEDs. People in the front will probably always see loss in quality compared to people in the back. With a laser projector that is not the case.

That is just assuming films are all 2D. How are you going to project 3D on it? You will either lose resolution or get terrible consumer like active 3D glasses with current technology.

It's a fun idea to discuss but in reality not doable (yet) for large theaters.
However- it might be a future for small cinema screens where there is plenty of space underneath the screen to speakers to go through. I am certainly seeing more home theaters going for the larger LED screens now that they are extremely flat.
Old 1 week ago
  #5
Lives for gear
Well, the cost of LEDs -- particularly surface-mount arrays -- keeps coming down. And I imagine theaters would be a lot easier to build if you didn't have to worry about projection. (Even a digital projector needs access.)

As far as center channel: there'd still be some spacing between surface-mount LEDs in an array; why not make the substrate perforated, and compensate for the additional audio loss in DSP?

A lot of this is currently impractical, but that can be because nobody's tried to develop a practical solution yet. It's not that long ago that theater experts were saying we'd never have projection digital cinema, because of resolution and brightness problems.
Old 1 week ago
  #6
Here for the gear
Quote:
Originally Posted by Jay Rose View Post
Well, the cost of LEDs -- particularly surface-mount arrays -- keeps coming down. And I imagine theaters would be a lot easier to build if you didn't have to worry about projection. (Even a digital projector needs access.)

As far as center channel: there'd still be some spacing between surface-mount LEDs in an array; why not make the substrate perforated, and compensate for the additional audio loss in DSP?

A lot of this is currently impractical, but that can be because nobody's tried to develop a practical solution yet. It's not that long ago that theater experts were saying we'd never have projection digital cinema, because of resolution and brightness problems.
In terms of costs I would (blindly) assume that replacing a LED wall is more expensive than fixing a projector in most cases. In a perfect world you don't have people throwing things at the screen etc. But it happens and sadly depending on area, a lot.
Also in a normal LED array you don't need as much pixels as the audience is standing far away enough (and honestly, even then you see the pixels.) When sitting close up the LEDs has to be really tight. Even if we could this (because at this moment the only screens "sufficient" enough to watch upclose decently are only this size and those still fail to represent colors correctly

Very costly if you want an IMAX sized screen and 3D will still be a problem regardless of pricing and maybe being able to put a sound system at the back.
Old 1 week ago
  #7
Lives for gear
Ah, but the LED 'wall' can be modular so individual sections can be replaced by the theater owner. The sections don't need bezels; surface mount devices can come up almost to the edge of the substrate.

As far as resolution: Pixels is pixels, and so-many-across means the same thing whether they're LED elements or projected. Though you might want a reflective substrate and slightly translucent, perforated surface in front of the LEDs to serve the same purpose as the slight blurring of pixels in a projected image. Or since the LEDs themselves are smaller than projected pixels, you might want to blur slightly in DSP.

The point is that these things aren't physically impossible. They're just more expensive and impractical today, compared to projection. (Digital distribution and projection was more expensive and impractical, compared to chemical film, a few years ago. A few years before that, digital intermediates were expensive and impractical compared to opticals...)
Old 1 week ago
  #8
Lives for gear
 
dr.sound's Avatar
 

The New Samsung LED Cinema Screen Issues that concern me:

Hard Surface The screen is a hard surface that will create issues sonically by bouncing off and reflecting sound from it to create comb filtering

Heat Unlike a Cinema Projector that is in the projection booth these units will be in the room and they will generate large amounts of heat. How do you cool them down and not make the Theater noisy?

Size These new units will not be as big initially as the large screens in Huge Theaters.

Cost The numbers i have heard thrown around are at a minimum $250,000 +, and this does not take into consideration install and Air Conditioning.

Security The signal to these units will have to come from the Projection booth so how do they deal with security of the signal into the back of the Unit?

Speaker Placement The only viable way of playing sound is by putting the center speaker ABOVE and BELOW the image. If you have ever heard a speaker configuration like this as a Mixer you wouldn't be happy with the sound of it!

Immersive Sound Like DTS X, Auro-3D and IMAX 12.0 and Dolby Atmos
To get an Immersive feeling you need Height Speakers. In the Auro, DTS X and IMAX 12.0 configuration there is a Height Center speaker ( a Height Left and Right on DTS X or Auro-3D) You will not get the perception of Height if you already have a Center Main speaker that is both above and below the screen. That leaves very little for an Immersive height or Voice of God speaker. Once again Sound takes a back seat!

Last edited by dr.sound; 1 week ago at 11:27 PM..
Old 1 week ago
  #9
Lives for gear
 

Quote:
Originally Posted by dr.sound View Post
The New Samsung LED Cinema Screen Issues that concern me:

Hard Surface The screen is a hard surface that will create issues sonically by bouncing off and reflecting sound from it to create comb filtering

Heat Unlike a Cinema Projector that is in the projection booth these units will be in the room and they will generate large amounts of heat. How do you cool them down and not make the Theater noisy?

Size These new units will not be as big initially as the large screens in Huge Theaters.
Weight?
Old 1 week ago
  #10
Gear Head
 

Quote:
Originally Posted by dr.sound View Post
The New Samsung LED Cinema Screen Issues that concern me:


Security The signal to these units will have to come from the Projection booth so how do they deal with security of the signal into the back of the Unit?
This one is easy to answer. SDI cables installed into dedicated channels. SDI supports insane sizes of uncompressed video, even more in paired line setups.
Old 1 week ago
  #11
Here for the gear
Quote:
Originally Posted by Samlow View Post
This one is easy to answer. SDI cables installed into dedicated channels. SDI supports insane sizes of uncompressed video, even more in paired line setups.

Not as easy for SDI. When you run cables for over 200ft you'll get in problems and the only fixes are degrading your final image if you really want SDI.
The only way I could manage to get over 400ft of SDI was using very low datarates which isn't optimal.
You could always go for fiber optics which fixes the problem of length.

Since there is usually not enough space underneath a room or at the back of the screen, having a "projector room" closer is not an option unless building from scratch.
Old 1 week ago
  #12
Lives for gear
 

Quote:
Originally Posted by Samlow View Post
This one is easy to answer. SDI cables installed into dedicated channels. SDI supports insane sizes of uncompressed video, even more in paired line setups.
Now how does that increase security? Two unencrypted cables are safer than one? ;-)
Old 1 week ago
  #13
Gear Head
 

Quote:
Originally Posted by RobinL View Post
Not as easy for SDI. When you run cables for over 200ft you'll get in problems and the only fixes are degrading your final image if you really want SDI.
The only way I could manage to get over 400ft of SDI was using very low datarates which isn't optimal.
You could always go for fiber optics which fixes the problem of length.

Since there is usually not enough space underneath a room or at the back of the screen, having a "projector room" closer is not an option unless building from scratch.
Theres fiber options for the SDI standard too, but yeah.

In terms of security, if you want ultra low latency, there's not many encoded options. Security would be physical. Install the cables in the walls. If people want to tap, they have to go to the connection on either end, or they'll have the signal fail as they cut your wires. Give someone a chance to drill holes in your walls and youve got a different problem altogether.
Old 1 week ago
  #14
Lives for gear
 

Thread Starter
As for security, of course you can have a data decoder at the screen position instead of in a projector. The decryption card inside our projector is not what I'd call big nor creates much heat. Running encrypted DVI on a fiber ought to work.
So I doubt that would be one of the hardest parts to solve technically. Many other valid arguments that speaks against a LED wall, but that really can't be a strong one IMHO (as a know-all without actual knowledge...).
Old 1 week ago
  #15
Lives for gear
 
pethenis's Avatar
 

Old 1 week ago
  #16
Lives for gear
Quote:
Originally Posted by pethenis View Post
Maybe these guys have the answer soon:

Technology - Audio Pixels Limited
That's fascinating.

I've seen similar arrays (or maybe licensed from them) in directional speakers.

The limiting factor with current technology seems to be getting a reasonable SPL without distortion. Their site clearly says power is proportional to the number of micro-transducers... and that non-linearity increases as you add more of them.

So for now, they look like a cute approach for tiny speakers in phones and tablets. But tomorrow...?
Old 1 week ago
  #17
Lives for gear
 
pethenis's Avatar
 

As I understand it, they claim 80 dB from one chip, 1mm thick.. now at what distance and how clean that is... impressive anyway
Old 1 week ago
  #18
Lives for gear
 
dr.sound's Avatar
 

Does look interesting. Now let's hear them for ourselves. I don't see anything here on their site on existing locations or implementations in a commercial venue. Right now it looks like theory.
Old 1 week ago
  #19
Lives for gear
Pethenis, where do you get that 80 dB figure? I couldn't find it anywhere on their site-- not in the technology description, not in their press, not in their CEO presentation.

And is it 80 dB SPL? Or are they claiming 80 dB s/n or dynamic range?
Old 1 week ago
  #20
Lives for gear
 
pethenis's Avatar
 

Quote:
Originally Posted by Jay Rose View Post
Pethenis, where do you get that 80 dB figure? I couldn't find it anywhere on their site-- not in the technology description, not in their press, not in their CEO presentation.

And is it 80 dB SPL? Or are they claiming 80 dB s/n or dynamic range?
Audio Pixels Holdings Limited Announces Performance Specifications
Old 1 week ago
  #21
Lives for gear
Help me out, here.

The text of that news release says 80 dB SPL for 250 Hz at one meter. But the graph of (actual?) results seems to show 60 dB at that frequency... a significant difference.
Can somebody reconcile that for me?

It does show a theoretical 80 dB SPL for a 16-chip array. But their site says distortion goes up as you add chips. And we don't even know how much the single chip was distorting in their 60 dB SPL measurement.

The straight line pressure v frequency looks strange, until you realize this is a system with essentially no resonances. So that's cool... assuming that the chips will be able to take the additional voltage as inverse of frequency when you attempt to flatten the response.

It's a wonderful concept and has lots of promise, but clearly a work in progress. (Early theater horns were pretty awful, but look how far they've come.)
Old 1 week ago
  #22
Lives for gear
 
pethenis's Avatar
 

Can't help you out Jay, just thought it was an interesting concept. Sending off a mail to see if they are willing to explain.
Old 1 week ago
  #23
Gear Maniac
 
Farhoof's Avatar
 

Quote:
Originally Posted by Jay Rose View Post
Help me out, here.

The text of that news release says 80 dB SPL for 250 Hz at one meter. But the graph of (actual?) results seems to show 60 dB at that frequency... a significant difference.
Can somebody reconcile that for me?

It does show a theoretical 80 dB SPL for a 16-chip array. But their site says distortion goes up as you add chips. And we don't even know how much the single chip was distorting in their 60 dB SPL measurement.

The straight line pressure v frequency looks strange, until you realize this is a system with essentially no resonances. So that's cool... assuming that the chips will be able to take the additional voltage as inverse of frequency when you attempt to flatten the response.

It's a wonderful concept and has lots of promise, but clearly a work in progress. (Early theater horns were pretty awful, but look how far they've come.)
Notice the "[1]" in that text.

[1] Normalized to 10cm, the conventional measurement distance cited by most micro-speaker manufacturers
Old 1 week ago
  #24
Lives for gear
Thanks, Farhoof, for pointing out the footnote that 80 dB is normalized to 10 cm. Okay, a 1:10 distance difference is 20 dB (or close enough).

So with a lot of equalization, a single chip would be suitable for a phone or close-listening speakers... assuming tolerable distortion levels. We still don't know what happens to that distortion when you build an array loud enough for any other purpose, but they do warn it'll go up.

Definitely worth keeping an eye on for future developments. Maybe -- just maybe -- it'll become mature enough for theatrical use around the same time direct LED screens are!
Old 2 days ago
  #25
Lives for gear
 
jwh1192's Avatar
Quote:
Originally Posted by dr.sound View Post
The New Samsung LED Cinema Screen Issues that concern me:

Hard Surface The screen is a hard surface that will create issues sonically by bouncing off and reflecting sound from it to create comb filtering

Heat Unlike a Cinema Projector that is in the projection booth these units will be in the room and they will generate large amounts of heat. How do you cool them down and not make the Theater noisy?

Size These new units will not be as big initially as the large screens in Huge Theaters.

Cost The numbers i have heard thrown around are at a minimum $250,000 +, and this does not take into consideration install and Air Conditioning.

Security The signal to these units will have to come from the Projection booth so how do they deal with security of the signal into the back of the Unit?

Speaker Placement The only viable way of playing sound is by putting the center speaker ABOVE and BELOW the image. If you have ever heard a speaker configuration like this as a Mixer you wouldn't be happy with the sound of it!

Immersive Sound Like DTS X, Auro-3D and IMAX 12.0 and Dolby Atmos
To get an Immersive feeling you need Height Speakers. In the Auro, DTS X and IMAX 12.0 configuration there is a Height Center speaker ( a Height Left and Right on DTS X or Auro-3D) You will not get the perception of Height if you already have a Center Main speaker that is both above and below the screen. That leaves very little for an Immersive height or Voice of God speaker. Once again Sound takes a back seat!
Spwaker Placement !!! what the Doctor said ..
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump