New Mac Cinema Display (LED backlit)

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MrPatate

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http://www.apple.com/displays/specs.html
New from Apple, 24'' 1920x1200 LED backlit
  • Display colors (maximum): 16.7 million
  • Viewing angle: 178° horizontal; 178° vertical
  • Brightness (typical): 330 cd/m2
  • Contrast ratio (typical): 1000:1
  • Response time (typical): 14 ms
I haven't been here often in the last months, the last time I was here, alot of people were talking about the next generation of LCDs with LED back lighting.
I don't know if there's alot of those new LCDs out, but it's the first one I see.... Though you guys might be interrested!

Not a big fan of Apple, but they sure do have good design(well, I just hope they will someday stop with that white trend thingy..... BLACK is the only color acceptable for electronics! ;))

The specs looks like the "usual" LCD, except the respond time which is a bit slower than what's generally on the market now, but shouldn't be a big problem....
 
I think they're using LED as a marketing tactic on a mediocre panel. We'll find out eventually though I guess when someone takes the plunge
 
I don't think that it is a mediocre panel. Those specs look suspiciously like and S-IPS or maybe the same H-IPS that's in the iMac.
 
LED = super noisy monitor

I can't wait for apple fans to start crying (me too since I hate noise).
 
astrallite said:
LED = super noisy monitor

I can't wait for apple fans to start crying (me too since I hate noise).
Click to expand...

Why are they more noisy?
I don't know much about those types of display, but I never eared a led making noise ;).... Is it because of the power supply they need or something related to that?(the only sound source I can think of right now)
 
too bad at the moment the only computers it can work with are the new silver macbook and 15" macbook pro.
It only has 1 connection, a proprietary mini displayport.
Apple doesn't have any adapters to make the screen work with any other interface(not even regular size displayport).
The only adapters they released are to make the new notebooks work with non mini displayport screens.
 
MrPatate said:
Why are they more noisy?
I don't know much about those types of display, but I never eared a led making noise ;).... Is it because of the power supply they need or something related to that?(the only sound source I can think of right now)
Click to expand...

Packing a ton of LEDs adds a ton of heat which require fans.

Apple still uses the "neolithic" external power brick with their monitors. Well the neolithic system was much quieter, cram a vibrating transformer in a monitor and you got a ton of noise. Factor the internal power supply & fans, and the LED backlit monitors out there are "extremely" noisy. It's kind of like a plasma TV, except you sit about 10 feet away from a TV and you're usually not doing something quiet like reading a webpage.

The reason I sold my NEC LCD2690wuxi (it was a dear monitor) but it the transformer noise was driving me crazy, and I had the monitor at 8 feet away. I've got a 47" LG LCD TV now instead, its much quieter, simply because there's so much mass strapping the transformer down that the vibration is nearly inaudible. I didn't even have a dud LCD monitor either, none of those backlight buzzing problems that other people had. The ambient noise the monitor put out was just killing me since I have a silent PC and my walls are super thick.

There's actually a bunch of university white papers out there talking about the massive problem of internal power supplies that LCDs use which (if you have good hearing and low ambient noise), the noise level is completely unacceptable.

Here's an excerpt:

"The frequency, in order that the flickering of the LCD string is not detectable, must be above about 50Hz (e.g. 300Hz). These frequencies however are in the audible frequency range. Ceramic filtering capacitors tend to display piezoelectric qualities and therefore, when the PWM output voltage signal is at an audible frequency, a buzzing noise is emitted by the capacitor as a result of its continuous deformation and reformation. This noise is not acceptable.

"One possibility used to overcome the problem of the audible buzzing of the capacitor is the use of tantalum capacitors instead of ceramic capacitors. However, although these have better resonance characteristics, they are also much more expensive and have other drawbacks such as having high effective series resistance (ESR). A further possibility is to modulate the DC current through the LCD string, instead of using PWM..."

Basically the issue is, power transformers make noise. You can use higher quality parts but the cost would go up like crazy. Alternatively, per a CNET article, you can strap the transformer down with a ton of tape and sound absorbers, but you have to compare pros and cons of greater weight of a display vs noise...

Of course if you use a low power TN monitor you'll never hear a peep.
 
Uberbob102000 said:
I don't think that it is a mediocre panel. Those specs look suspiciously like and S-IPS or maybe the same H-IPS that's in the iMac.
Click to expand...

whoa the imac is an IPS? that's a bit disconcerting...i've used the ones in the library fairly extensively...the color on them is terrible and shifts all over the place. it's impossible to get a page to look right. it's better than the TN dells but only barely.

i hope the 3007 (or this new display) doesn't look like the iMac...iirc it's an S-IPS but i don't know the differences between S-IPS and H-IPS.
 
Yeah I think the imacs use either TNs of VAs...the ACD (Apple Cinema Displays) use S-IPS panels, although the electronics driving them are extremely outdated which is why they're about as visually unimpressive as you can get for IPS screens.
 
Uberbob102000 said:
LED don't make that much heat at all compared to CCFL :confused:
Click to expand...

That's correct. LED backlights consume less power and generate less heat than CCFL backlights. Also, they are not noisy in any way. Power supplies can be noisy when poorly designed, but I've never heard of a noisy LED backlight.

I have a 30" Samsung XL30 which has an LED backlight. It's the coolest-running monitor that I've ever had. Monitors with the same exact panel with a CCFL backlight (Samsung 305T+, 30" Eizo monitors) generate noticeably more heat.
 
astrallite said:
Packing a ton of LEDs adds a ton of heat which require fans.
Click to expand...

Not really. They generate less heat overall than CCFLs for the same amount of light. The reason some monitors with an LED backlight contain a fan is that LEDs are much more sensitive to heat than CCFLs. Heat affects the light output of the LED as well as its longevity. The fan typically stays off until the temperature rises beyond a certain level. I have never heard it kick in on my Samsung XL30. The only time I hear the fan is when I turn on the monitor and the fan goes through its power-on testing, and then the fan is turned off. On my Eizo CG301W which uses the same panel with a CCFL backlight, there is also a fan, and it stays on all the time.
 
14 ms .. unacceptable. Even for basic users thats just ghost city in this day and age and thats only typical response time to boot.
 
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