dvi, hdmi players not for crt? (1 Viewer)

[allan espinoza]

hi, i keep hearing that dvd players with an hdmi or dvi output are best when used with an lcd, dlp or plasma tv, but for anything else like a crt you should just stick with a progressive scan dvd player. is this true and why? am i loosing any video quality? i have notice that when using dvi through my dvd player, letters appear to be a bit blurry compared to component where it is a bit sharper? any input on this?

 

[Jerome Grate]

The concept behind that belief is that lcd, dlp and plasma are fixed displays as oppose to crt. DVI and HDMI are digital video connections and CRT are analog video projection. For your CRT based t.v.s it has to process the video signal through analog to digital and then back to analog which involves some degradation of the picture during the process. It is said that since lcd, dlp and plasmas are fixed displays the digital to digital direct connection gives a better picture without the a/d and d/a processing. But some of the testimonies here and other forums is that the diffence is nominal at best. All depends on the t.v.

 

[EricRWem]

I always use digital whenever I can, regardless of display. Even CRT's see some sort of benefit. If you have it, use it!

 

[allan espinoza]

well the tv im using is the sony kv-36hs420 and when using the dvi out from my player(samsung hd 841) to hdmi in on my tv i always felt as the image appeared to be somewhat blurry, kinda like when you crank up the sharpness too high, but the image and colors were brighter though and looked nice especially when upconverting to 720p or 1080i, although only downside is that whenever i would upconvert it would stretch out the image and looked kinda funny. but when using a component connection i notice more detail in the picture with colors and black levels down a notch, a bit more video noise and lettering appeared to be sharper. i cant stop thinking that i feel as if the picture looked better on my old sony which was like 10yrs old because i would never see any video noise or problems i am facing today with my new tv. i wonder why? could it be the dvd player that degrading my tv? what do you guys think?

 

[allan espinoza]

whats a good player with a good component connection?

 

[Allan Jayne]

So you are saying the same DVD player connected to the same TV using component connections gives a sharper picture compared with DVI connections?

There must be some processing in the digital signal path that is inferior compared with the analog signal path, probably somewhere in the TV.

All digital video formats have both a horizontal and vertical pixel count. If your TV has a native horizontal count that differs from that of the DVD player, there will be a quality robbing conversion.

Analog formats have a vertical count (scan lines) but do not need upconversion or downconversion in the horizontal direction. But if the TV only displays in 1080i/540p or 720p or 768p then incoming 480p must be upconverted requiring digital conversion and a horizontal pixel count will be imposed.

Video hints:
http://members.aol.com/ajaynejr/video.htm

 

[EricRWem]

First thing I'd say to you is get rid of that Samsung 841. That player is a dog, with black crush and plenty of other video problems that are well documented at places like hometheaterhifi.com's Secrets test pages.

That nice Sony TV hs420 has circuitry in it that's going to have a field day with most signals you throw at it. You would have to climb up the ladder CONSIDERABLY, in terms of upscaling players, to find something that has superior technology to what your TV can do right now. The Sammy 841 sure as hell ain't that!

Now, if you want upscaling, you may find matching Sony with Sony to be quite successful. By this, I mean trying out the Sony 975 on your HS420. I think you might be real pleased with the results of that match.


It doesn't surprise me, in some cases, that the component PQ is better. Certainly the 841's myriad of flaws over the digital connection are well documented, starting with the trademark Samsung black crush.

But the other reason can be a much broader one: Because you're not getting a potential conflict and "video noise" from TWO devices trying to do something with the PQ vs. just one.

I'd say to you, maybe consider an awesome pro scan player like a Denon 2900 (shop around it's in the $600's give or take. Ecost has it in the $500's.)
or a Cambridge 540d (under $400, AWESOME!!!) for that Sony. For the Cambridge, you're paying money for just a top notch pro scan DVD picture and really good CD player vs. the Denon 2900, which you're also going to be paying for high-rez audio. Now, I love high rez audio and will push it on anyone, but there are your differences.

 

[Seth_L]

The premise is crap.

Any modern CRT set converts any incoming analog signal to digital. If you feed the set a digital signal (DVI or HDMI) you bypass that extra analog to digital conversion. There's no way that can be a bad thing.

 

[EricRWem]

 

[ChrisWiggles]

What? And why would it convert the signal into digital just to convert it back to analog.

You're being totally illogical, plus not correct. If there was a set that was converting things digitally, then back to analog, I would probably avoid it.

The best CRT displays in the world don't convert things to digital. Digital control, yes, but no digitization of the signals, as the whole display system is by it's very nature analog in behavior.

 

[ChuckSolo]

I gotta chime in here. First of all, you can have all the reviews in the world, but until you try personally try the product, how can you say it is crap? I have a Samsung 841 plugged into my RCA HD RPTV's DVI port(also continually called crap on these boards) and the output from the Sammy to the TV is excellent. First of all, you are ouputting a DVI connection to an HDMI one, correct? Maybe that's the problem. I would assume you are using some kind of adapter to convert the DVI cable so it will plug into your TVs HDMI port, is this correct? Digital to analog, analog to digital, whatever, all I know is I have the products and they perform as advertised. I have had my RCA TV now for almost a year with NO problems at all. I have had the Sammy now for almost 90 days, with NO problems at all. I watch at least 2 DVDs a night, disliking most TV programming with the exception of the CSI shows and CBS' Monday night line up. The fabled "black crush" and all the other "urban legends" regarding the Sammy and the unreliablility of RCA TVs is crap, I have both and they are fine! Instead of lecturing Allan to get rid of his Samsung, which probably cost him at least 200 bucks, let's try to help him with his problem. I believe it to be the DVI to HDMI connection. I have a DVDR connected to the component inputs on my TV and my Sammy to the DVI input. I have compared the picture coming from both and the DVI connection is, on my TV anyway, superior. Allan, since your TV does not have a native DVI port, only an HDMI, there is no way to really know if it is the player or the TV. I know, I know, you are all gonna tell me I'm one of the lucky ones since I haven't had any problem with either my RCA or Sammy.........sigh.:frowning:

 

[Kevin C Brown]

Seth- If I feed a progressive signal to my TV (Toshiba 32" HDTV), it doesn't need to convert it to digital then back to analog. But does it? Any other TV accepting a 480p signal I imagine would do things the same way.

 

[ChrisWiggles]

I will add to my post, because I forget sometimes that I'm dealing with consumer displays! Duh chris! :b

The video processing and upscaling functions will do their processing digitally in the set I'm assuming usually. Forgot about that part.

So I am backtracking significantly on my last post. The actual workings of the display portion of the set will be analog, but with digital controls usually for convergence, etc etc. The video processing is something I sort of consider as an "exterior" part separate from the display, because I would use other better processing methods when possible to bypass on-board video processing, but that's just me.

So don't take my last post harshly!

 

[Phil Nichols]

Eric,

"How to spot a weak argument:" Interesting list, but I wonder if it's academically sound?

Now about how a matching list of "How to make a strong argument:" - without consistingly only of the usual stuff such as:

- "the scientific method"

- "facts/facts/facts"

- "data/data/data"

- "etc."

which is very time consuming and/or expensive for a lot of us to get involved in every time we want to make a point.


Chriswiggles,

"You're being totally illogical, plus not correct."

I'd like to think that a pure unprocessed analog video channel is the case with my Pio Elite CRT RPTV which renders spectacular analog component 480p from a player with Si504 deinterlacing .... but I'm afraid that things like 72 point dynamic convergence control, 256 steps of sharpness control, 256 steps of black level control, 256 steps of contrast control, 256 steps of horizontal detail control, multiple color temperatures, 3:2 pull-down, and PC overlay image control ..... may require direct digital intervention/conversion/deconversion in the analog video stream.

Do you think things such as the above can leave the analog video as direct and unprocessed? If analog -> digital -> analog converison is being used in this case, then Pio is certainly dealing with the conversions and processing about the best that they can be.

(Perhaps I'll have to study my schematic of the set to see where and how much digial intervention is being used!)

 

[EricRWem]

I was giving Seth the for this specific statement:

You're damned lucky. I can't comment on your TV, but as for that 841? Wow, you're lucky! That 841 is a dog and that's a well established, well documented FACT. Have you had a DTS audio drop out happen to you yet on it? That's another well known, common plague that a lot of now former 841 owners have complained about as well as professional documentation.

I have a Zenith c32v37 HD CRT tube. I've always used DVI at every oppurtunity. I have a great picture. I do see refinements and improvements over DVI vs. component. Using digital inputs is ALWAYS a good thing if you have them available to you.

 

[ChrisWiggles]

Phil: I'll explain even a little bit further, why I "forgot" about on-board processing, and then also what the set is doing.

I use a CRT projector, which is just a display that takes RGB input, and can display HD resolutions, etc, but it has NO-onboard video processing, it is just a display like a computer monitor. It displays what I feed it.

It's the video processing part of consumer HDTVs that will be digitizing the signal to upscale the video, and for this reason, it may be slightly beneficial to use a digital connection to avoid a D-A conversion out of the source, then an A-D conversion in the set. REgardless, with CRt, there will ALWAYS be one final D-A conversion to drive the guns which operate in analog of course.

As for the in-set adjustments and menus, these *are* operated digitally, but these drive signals that either affect the analog video signal that is fed to the yokes, or the beam currents, or whatnot, or perhaps an EM focus coil if present. These are digitall *controlled,* but implemented to affect the analog signal.

So you can think of it as a digitally controlled analog display. The very old sets did not have digital controls, menus etc, and were all-analog chassis. To adjust convergence, etc, there were banks of adjustment pots that you would turn with a screwdriver, that would control these adjustment voltages and signals. Now, this is all done with menus, which are operated digitally, but back in the day, this wasn't the case.

the basic operations of a CRT, are, however, analog. And mine, which has no on-board processing, gets fed a signal from my HTPC, and this stays in analog all the way until I see it on the screen. The adjustments, menus, etc, are all operated digitally, but again, these all control the insertion of analog waveforms to various parts of the video signal, and other signals such as the focus coil, to display the picture, but the video signal itself is not being digitized at all.

 

[EricRWem]

I almost didn't see this gem:



*Holds hands up innocently*
Hey, I didn't write that thing! But that is a very interesting idea. That's why it's just a lone link way out of the way. I find that I've needed it several times around here, when tempers start flaring. I find that item 1, in particular, makes itself known and then gets shot down.

 

[ChuckSolo]

Eric, define hordes. Have you tried the Samsung? Have you ever had an RCA TV? If the answer to these questions is "no" then you are not qualified to call anything crap. Second, have any of you ever taken a class in statistics? I did as part of my BS in computer information science. If you have, then you will know that a random sampling of ANY object or product is NOT conclusive evidence of anything, but the only way to get a "nebulous" idea of how a product or object will perform. The keyword here being "idea." Out of the hundreds of thousands or even tens of thousands of units of this product that Samsung has produced, how many do you think have been sampled? I'll bet it's way less than you might think. I am not angry about it at all. I don't care what hometheaterhifi.com said in their "shootout" random samplings of any product are "crap." In order to give an objective, definate and conclusive statement to their shootout, they would have had to test more, way, way, way, more than one sample of each player to come to a proper conclusion. Any real "expert" would know this. Eric, don't take as gospel everything you read, those "shootouts" can be skewed anyway the tester wants. Take a modern class in statistics and you won't be tempted to believe everything that is published by the "experts." Even a magazine like "Consumer Reports" can't possibly test a product like it should to make positive or negative conclusions. All of those tests are "probability" tests....no more, no less. If you ain't got the product, don't judge, because you can never really know, until you try them yourself.

 

[Phil Nichols]

ChrisWiggles,

You reminded me that on my Elite RPTV I do have a pure RGBHV input that is left alone all the way to the guns. I've tried it once for HD from my DISH STB, but no image adjustment is permitted by the RPTV.

I wonder how this would look for DVD's?? Interesting idea. I don't use it currently, but I suppose I could use a component-to-RGBHV converter box and feed my Denon 3800 DVD player's output into it.

I've studied the specs a bit for the Sony's outstanding G90 CRT front projector. This projector must accomplish all of it's sophisticated control using digital. i.e. Controls that "square up" the image, regardless of the projector's angle of attack to the screen (trapezoid correction, etc.).

 

[Seth_L]

If you say so.

Go look at any recent Hitachi RP CRT, or a Sony 34" XBR960 or lots of other CRTs. They do indeed digitize any incoming analog input and run it through the processor they spend an aweful lot of time bragging about in their literature.

I know for a fact that my Hitachi RP CRT 57S715 has a Pixelworks engine/scalar. It does all the de-interlacing and scaling (PiP and what not) for the set. Using picture and picture I can place an analog 1080i source side by side with a DVI 720p source. There's no way the set can do that unless it is digitizing the analog input.

Why do you think recent CRT TVs don't show both 1080i and 720p natively? Because the sets are scaling all the inputs and are only outputting a single resolution to the tube(s).