between looking through a photographic slide held up to the sun or a bright light (which gives you all the dynamics of transmitted light), vs. looking at the same slide projected up on a screen (which gives you merely the dynamics of reflected light).
Its color saturation, accuracy, and gradation have steadily improved over the years, to a superb standard of excellence in better units. Bandwidth and resolution have likewise steadily increased, so that direct view CRTs (especially those built for laboratory or professional use, as well as consumer high definition sets) can resolve more and finer information than other display types. Problematic issues such as linearity, tracking, focus, and convergence have been progressively reduced to near insignificance over the years.
Cost is very reasonable. And they're dead quiet, with no fan noise.
So what's not to like?
The screen size is too small. And the box size is too big.
The high definition 16:9 direct view TV sets portray a beautiful quality image. But the biggest tubes are about 34 to 36 inches diagonal. And this is far too small to achieve believability, especially because of the puny height problem. As noted above, on such a screen, heroes in a movie stand no taller than they do on a 27" TV set, and visually they look even shorter than that because their height is now psycho-visually compared against the vast horizontal expanse of the scene portrayed on the 16:9 34" screen.
You could try sitting up closer to the screen, as you can with a plasma display, but that doesn't work here because the direct radiation of the CRT is visually irritating, fatiguing, and possibly even dangerous when viewed too closely.
You could try instead getting a 4:3 aspect ratio TV set, which is available up to 40" and of course does present a much taller image - until you letterbox it to watch your widescreen movie. Additionally, these 4:3 sets have only moderate resolution, not true high definition resolution (though their picture quality can still be excellent, within the context of their lower resolution).
And of course the box size is too big, specifically too deep, for such small size screens. As you know, this depth is required by the internal geometry of the cathode ray tubes, to furnish the performance they do.
If you don't mind the small screen size, then some direct view CRT sets are highly recommendable for their image quality. In high definition 16:9 sets, Sony and Loewe make good looking products. In the moderate definition 4:3 format, our favorite is the Sony XBR flat screen (aka Wega).
-- Integrated Projection TV Sets
This display format is far and away the most popular among the masses who aspire to grander video. This is what big screen means to most people. So I apologize in advance for offending so many of you, because I must tell you that the video quality on most of these sets absolutely sucks. Even basic things that every modern video system ought to get right (like focus, video noise, and video distortion) are generally awful. And the noble videophile desiderata like contrast, resolution, color rendition, etc. are generally equally bad.
What else could you expect, really? These sets are designed (if that) and built to a strict penny pinching budget, to be able to offer the most screen size for the fewest bucks, to an audience who cares only about screen size and bucks, and who doesn't know or care about video quality.
Having said that, and having not said a lot more I could say in justifiable derision, there are a few exceptions. Some among the newest 60"+ HDTV 16:9 projection screen integrated sets offer decent video quality, and a lot of bang for the buck. These sets generally claim 1080i resolution capability, and sometimes include decent quality de-interlacers and scalers to improve the appearance of various inputs, including 480i DVD (if the de-interlacer in a progressive DVD player proves superior to that on board the TV set, you can output 480p into these TVs). They also now offer HDTV tuners on board (at least for direct local channels), so you can be ready to fly. The 60"+ screen size is impressive, meeting our requirement for losing yourself in the portrayed image and believing. You can sit up close if you want, because the image is projected onto a screen, not directly radiated at your eyes as with a direct view CRT. Also, the decent quality scaling to a high resolution picture, with low noise, means you can get close without being bothered by scan lines or other artifacts.
Rendition of color and luminance is actually pretty good on a few of these sets. So far, we like best the Thomson/RCA, the Sony, and the new Marantz (Mitsubishi, Panasonic, et al. have brash, noisy color and luminance renditions that lack subtle and natural believability). The scene portrayed on screen has a nice vividness and glow as a whole. The only thing really lacking is the differentiated inner glow of the various distinct faces and objects on screen, the gradation in color and luminance that should give each object in the scene a three dimensional reality and touchable palpability. Because of this lack, the portrayed scenes are vivid but two dimensional, and the faces and objects in the scene are merely part of the two dimensional curtain, rather than being three dimensional objects you can believe in (as you can on a 60" plasma from NEC or Revox).
The most wonderful thing about these few good quality projection TVs is their price. For about $3400 to $6500 you can get the whole works in a box: 60"+ display in 16:9 widescreen format, high resolution, and HDTV tuner thrown in. The volume efficiency of mass marketing does have its benefits, especially when it joins hands with serious efforts in designing better technology.
You can get a DVD player for about $100. So why should you spend $2500 or more? Because, for now, the link from DVD player to the rest of your system is analog. And analog video signals impose some tough requirements on circuitry (e.g. bandwidth and phase), if the signals are to be reproduced properly. Degraded video signals mean degraded images from your display. The best video believability is achieved when your system's video circuitry is engineered to respect the demands and the integrity of the analog video signal. And it can be expensive to execute this circuitry well.
We got a dramatic lesson proving this from Arcam's FMJ DV-27. For this flagship DVD player, Arcam went beyond the call of consumer electronics duty, and they brought in an engineer who designs professional video equipment. Basically, Arcam told this fellow to take what he knew and put it into the circuitry of this DVD player. The results speak for themselves. We were amazed at the video quality and sheer believability of the image sourced from the Arcam FMJ DV27, especially difficult human faces. The believability of the DVD's image was so extraordinary that it was convincing even on a moderate size display with only moderate resolution. That's what great video circuitry in a DVD player can do.
Other DVD players we have been impressed by include those from Theta, the new Marantz DV-12S1, the Philips Q50, and the forthcoming Denon 9000. Then of course there's the new Faroudja, with built in video signal processing by guess who. None of these are cheap. Every one is worth the money.
At some time in the future, when home video systems are digital throughout, this situation will change somewhat. But even then we will find that bits aren't merely bits, and that quality counts.
For example, most of today's DVD players have digital jitter that is far too high, much higher than in audio CD players playing essentially the same media. It's expensive to effectively minimize jitter in a DVD player, because of the added complexity of a unit that must clock video as well as audio signals. Combating jitter usually requires multiple separately regulated power supplies, multiple clocks or re-clocking buffers, careful shielding and isolation, low noise design (noise contributes to temporal uncertainty, i.e. jitter, in digital circuits), etc.
Why is low jitter important? As we explained in IAR issues #61, 62, and 71, so-called purely digital circuits are actually half analog. They are discretely digital along the amplitude axis (one half of the two axes needed to plot out a waveform on a graph or scope), but they are continuously analog along the time axis (the other half of the two axes). Jitter and noise produce unwanted momentary variations along this continuous analog time axis, affecting exactly when the digital signal is looked at and interpreted by later circuitry or human brains. Since the signal amplitude is continually varying, the exact timing of when you look at the signal unfortunately affects the apparent amplitude of the signal. In short, timing errors in the digital circuitry produce apparent amplitude errors later when the signal is interpreted, especially when it is converted from digital to analog and integrated, by conversion circuitry or by our brain.
Thus, even in our digital future we should still find need for premium playback sources that are engineered right, without consumer mass marketing compromises, and we should still be happy to invest in their higher price.
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