Collarspace Discussion Forums


Home  Login  Search 

CRT TVs versus Panel TVs


View related threads: (in this forum | in all forums)

Logged in as: Guest
 
All Forums >> [Casual Banter] >> Off the Grid >> CRT TVs versus Panel TVs Page: [1] 2   next >   >>
Login
Message << Older Topic   Newer Topic >>
CRT TVs versus Panel TVs - 12/28/2011 7:50:49 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline 		For all I know this question has been done to death on forums elsewhere but I was wondering how others feel about the quality of what I prefer to call “panel” (rather than “flat”) TVs (LCD, LED, and Plasma) versus traditional CRT (cathode ray tube) TVs? I refer particularly to the end of production CRT's which were visibly flat rather than curved as they had the best quality that CRT screens could offer. They appeared in the final half of the 90’s and were the predominant type in the new millennium.

I did a side by side comparison of a mid-priced Philips 32" LCD (1080p), and a fairly average Philips 21" flat CRT from around 2004, from the same reception source (mainly high-definition signals from a modern digital satellite dish). The LCD was appallingly blurred except for some high-definition programs and distant objects were very poorly resolved. Motion could be very juddery and notably blurred during fast movement, such as with hand movements across the screen with weather forecasters. Other than a slight flicker, the naturalness and sharpness of images on the CRT tube gave a new appreciation for that technology. Note the LCD was fed a high-definition signal while the CRT was fed a standard-definition signal via scart. It reminded me of something I heard about high quality CRT screens still being popular for programme production.

There are of course a number of technologies around at the moment, LCD being just one, so the above observation will have limited applicability as each technology will have problems particular to its own. Some plasmas do seem a bit better but I was never particularly impressed by the picture quality of any panel TV's although my own experience is limited, as being someone who doesn’t watch a lot of films, it only became more of a concern come to me recently when I bought two panel screens for other folk.

If the small test I did was reasonably representative of many screens then it leads an obvious question: are people being swayed by fashion and/or the desire to have less intrusive screens in their homes? If its true then it is unfortunate that all manufacturers appear to have abandoned CRT technology.

It would be interesting to know what others think. Panel TVs definitely have advantages. Big tube TVs were more expensive to produce (after the more expensive introductory phase of the various panel technologies), bulky, energy inefficient and very heavy (a hernia inducing 60 KGs for many a 32”) but do you chaps think panel TVs give better picture quality or just take it for granted that they're better? If you think tubes are better, are you happy enough with the quality of panel TVs not to care too much?

< Message edited by Anaxagoras -- 12/28/2011 8:47:15 PM >

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)
Profile   Post #: 1
RE: CRT TVs versus Panel TVs - 12/28/2011 8:35:24 PM   
Toppingfrmbottom


Posts: 6528
Joined: 6/7/2009
Status: offline 		I think that when LCD tvs get insanely huge like 50 to 60 inches, then picture quality suffers, but I can't wait to be able to afford a new flat screen tv, cause my regular big boxy 25 inch tv don't cut it any more in terms of being able to read font on it, and my parents have a flat screen 32 inch that i can read just fine and has a very nice pic on it.

_____________________________

One world under lube with vibrators and dildo's for all! quote from the sex toy 101 book

(in reply to Anaxagoras)
Profile   Post #: 2
RE: CRT TVs versus Panel TVs - 12/28/2011 9:03:35 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline 		Kinda moot point since there are no more CRT TVs.

Later CRTs were always better. A plasma is nothing but a squished CRT with a really special grid. An LCD flat is like the old calculators. A projection LCD is junk and all DLPs and projections that are NOT CRT based are junk because of the limited bulb life.

What would have been nice is if they had taken VFD technology somewhere but there are obvious reasons for not doing that. It would simply be too reliable.

All of these new technologies have one thing in common, unrepairablility and unreliability. It 1977 you could get a sharp enough picture even without a COMB filter that was bright enough to watch in direct sunlight that only consumed about 190 watts and lasted ten years. Only 50 - 80 watts of that power actually reached the screen. The rest was eaten by deflection circuits which were heavily taxed by wider deflection angles (slimmer cabinet depth) and ultimately HD. They had plenty of 1080i CRT sets, but I dare you to find a 1080p CRT set. You can't because the H sweep frequency would be too high. Being an inductive load, yoke impedance has been reduced to a minimum and just to do 1080i it needs a thousand volt pulse. Double the frequency and you need to either half the impedance or double the voltage and neither is practical with today's semiconductors, at least within any reasonable budget.

Plasma was an attempt to eliminate the deflection and put most of that power to the screen but it didn't work out and now they are still less efficient than LCDs or either type or DLPs. In fact the EU considered banning them for inefficiency, but I doubt that ever happened or will.

Consider this - any LCD or DLP does not produce it's own light, it needs a backlight like a film projector. That means the light source is running full blast all the time. You turn a plasma or CRT set brightness/contrast down it runs cooler and uses less electricity. You turn down a DLP or LCD and it runs hotter. This does not seem very efficient to me at all, however everything else seems to be worse. In other words engineering has failed us.

Some advancements have been made with the CCFL/LED hybrid backlit and the totally LED backlit sets. They can modulate the backlight, which has the desirable side effect of enhancing the contrast ratio. The newer LED lit sets should be a bit more reliable as well, if for no other reason than the rest of the technology in the set is older. (good enough LEDs for this application used to be too expensive)

The fact is that CRT beats them all. But the problems involved with deflection and geometry cost money to resolve, and the bottom line was hurt. LCD and DLP sets should be dirt cheap, but they are still "amortizing R & D costs" which basically means making a shit load of money while the gittin' is good.

They will be amortizing R & D costs until people are weaned from their addiction to the boob tube.

Wanna buy a Barco IQ Pro G 350 ? I got two of them. Kickass sets but I have no use for them, and being projos, I mean wall projos, I just don't need the hassle of making space on a wall or something on which to project the image. Plus I am simply not enamoured with the thing anymore.

T^T

(in reply to Anaxagoras)
Profile   Post #: 3
RE: CRT TVs versus Panel TVs - 12/28/2011 9:26:35 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline
quote:

ORIGINAL: Termyn8or
Kinda moot point since there are no more CRT TVs.

I wouldn't agree with that because there are a huge number of CRT TVs out there still, many of which are on sale for the equivalent of pennies so it may be a great time to buy!!

quote:


Later CRTs were always better. A plasma is nothing but a squished CRT with a really special grid. An LCD flat is like the old calculators. A projection LCD is junk and all DLPs and projections that are NOT CRT based are junk because of the limited bulb life.

I'm not hugely knowledgeable on this but as far as I understand it, both have charged elements so have some smiliarity but plasma TVs are roughly based on flourescent tubes, where negatively and positively charged atoms slam into each other releasing light, while CRTs are based more on the old light bulb where electrons from a cathode to the anode.

quote:


They had plenty of 1080i CRT sets, but I dare you to find a 1080p CRT set. You can't because the H sweep frequency would be too high. Being an inductive load, yoke impedance has been reduced to a minimum and just to do 1080i it needs a thousand volt pulse. Double the frequency and you need to either half the impedance or double the voltage and neither is practical with today's semiconductors, at least within any reasonable budget.

You could try a tube power supply. It would do the high voltage in its sleep but they haven't been seen in TV sets since the early 70's.

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)

(in reply to Termyn8or)
Profile   Post #: 4
RE: CRT TVs versus Panel TVs - 12/28/2011 9:39:17 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline
quote:

ORIGINAL: Toppingfrmbottom
I think that when LCD tvs get insanely huge like 50 to 60 inches, then picture quality suffers, but I can't wait to be able to afford a new flat screen tv, cause my regular big boxy 25 inch tv don't cut it any more in terms of being able to read font on it, and my parents have a flat screen 32 inch that i can read just fine and has a very nice pic on it.

I'm guessing you mean the panel TVs when you talk about flat TVs. I used panel rather than flat in my opening post because there are old style tube TVs that have a completely flat screen. I assume your boxy 25 incher is an oldish model with a curved tube at the front. If so, and you don't mind the bulk of tube TVs, check out a newer completely flat screen tube set. It could offer better picture than a panel TV and could be bought for a few cents second-hand! That is if America is like Ireland where people are virtually giving away high-end flicker-free (100/120 Hz) completely flat tube TVs that would have cost up to four figures five+ years ago for less than a hundred of Euros today!

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)

(in reply to Toppingfrmbottom)
Profile   Post #: 5
RE: CRT TVs versus Panel TVs - 12/28/2011 10:05:03 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline 		"because there are a huge number of CRT TVs out there still"

Not here unless you are talking about used.

"where negatively and positively charged atoms slam into each other releasing light, while CRTs are based more on the old light bulb"

Bad analogy. The CFL or flourescent of any type is essentially the same thing. It is diferent than incandescent of course but the CRT uses a tightly focussed beam which is deflected magnetically. *

"You could try a tube power supply."

Too inefficient actually. Even when replacement costs are included, because the cathode coating in vacuum tubes actually wears out.

* The phospour on the color TV screen is very similar to that of a CCFL or flourescent, and practically identical to the phosphors in a plasma. In either case producing this tight matrix of R, G and B pixels is no small task on a manufacturing level. Using a bulb eliminates that problem but the pixels are not individually modulatable, therefore an external method is needed.

The best but right now is probably the flat panel LCD that is backlit by LEDs totally. The LEDs have been improved and they operate on much lower voltages negating the need for DC - DC convertors, like the flyback would do. All projection sets have a major problem when it comes to lamp life, the parameters must be well controlled. The power supply (called a ballast in the US commonly) has to put out a constant WATTAGE. Through the life cycle of the projection lamp more and more voltage is required to run the lamp at the proper temperature. The glass actually gets fatigued.

In some older units the power ws not strictly controlled and as the lamp aged a decrease in performance would be noticable, however they took care of that. Initial customer satisfaction is most important so now it will burn down giving you a like new picture. They have a timer that tells you "REPLACE LAMP" and you damn well better do it. Otherwise it explodes, wrecks the housing and can fry the ballast. So they just tell you when you must reach into your pocket for a couple of hundred bucks.

It wasn't that different with CRTs. A long time ago the cathode coating was sort of a ceramic material to enhance electron emission. It took a minute or so for the filament to reach operating temperature though so for a time they had a preheat circuit that kept the filament partially lit while the set was off. This actually extended the life of some CRTs so of course that was unaccaptable. They found newer materials which worked fine, and actually better. They also reduced cathode mass for a couple of reasons. First of all they were sick of equalizing the capacitance in the video output stages and they could put the cathodes much closer together making convergence errors alot easier to design out. Actually it also allowed for a smaller diameter neck which placed the deflection yoke coils closer to the beams. If not for this the load on the deflection circuits would be too great to even get beyond 90 degrees.

But that is a tri gun direct view color CRT, what of CRT based projections ? Few of them even hit 70 degrees deflection but the density of the beam still taxed the poor transistors. But the main problem here is that it was electromagnetic deflection. Oscilloscopes have used electrostatic deflection for longer than I have been alive. There was no problem with geometry much due to long neck lengths but that can be corrected period anyway, a hell of alot easier than it could magnetically.

Electorstatic deflection should have been the way to go for CRT based projection TVs, hands down. I am well familiar with the designing problems, and IMO it would be as easy to surmount as the set of problems incurred using magnetic deflection. Further VFD technology should have been used for flat panel TVs from the very beginning, absolutely. What's more even I could've designed the drive circuitry to use induction, but this would not be anywhere near the power required by a conventuional deflection yoke.

If I thought I had a snowball's chance in hell I would patent it. Really, I would not even try to present it to industry. I don't feel like going to China, but then when they read my patent they would just steal the idea if it's worth it, and if it's not it is as useless an exercise in futility. I am just happy to let the world go down the "tubes".

All in all, you go in a TV store and you see lal these different brands (all three of them) and different technlogiers and see a difference in the pictures. But in your own home that does not mean shit. Some people go for the brightest, but I can tell you that color rendition and brightness output are inversely proportional. You can have the bightest thing on the planet, but if it can't reproduce dark (navy) blue, it simply can't. Just like speakers, you can read all the specs you want but you know damnwell not to buy anything until you actually hear them.

Same deal.

T^T

Edited to add that I am not editing all night. Sorry about the typos.

< Message edited by Termyn8or -- 12/28/2011 10:12:24 PM >

(in reply to Anaxagoras)
Profile   Post #: 6
RE: CRT TVs versus Panel TVs - 12/28/2011 10:22:29 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline
quote:

people are virtually giving away high-end flicker-free (100/120 Hz)


I imagine with the native 50 Hz rate, that was addressed earlier in that market as more people would undoubtedly notice the flicker. Even though films were only 24, the was the whole picture at once, while this was scanned. Before that they probably used longer persistence phosphours in the CRTs.

In the US it was 60 Hz so the effect was not as noticable. Some notice, some don't.

T^T

(in reply to Anaxagoras)
Profile   Post #: 7
RE: CRT TVs versus Panel TVs - 12/28/2011 10:22:47 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline
quote:

ORIGINAL: Termyn8or
"because there are a huge number of CRT TVs out there still"

Not here unless you are talking about used.

Indeed I am. Nothing wrong with second-hand if it offers the best picture at a small fraction of the price. Many people who spent a lot on a high-end widescreen would care for it.

quote:


"where negatively and positively charged atoms slam into each other releasing light, while CRTs are based more on the old light bulb"

Bad analogy. The CFL or flourescent of any type is essentiall the same thong. It is diferent than incandescent of course but the CRT uses a tightly focussed beam which is deflected magnetically. *

The flourescent tube comparison is often cited as a comparison with plasma http://electronics.howstuffworks.com/plasma-display1.htm - the CRT tube to the old fashioned light bulb is my analogy, and while it is simplistic both are fundamentally based on the same technology. Edison invented the light bulb and soon stuck another element (collector) inside.

quote:


"You could try a tube power supply."

Too inefficient actually. Even when replacement costs are included, because the cothode coating in vacuum tubes actuall wears out.

Not for a tube rectifier.

quote:


But that is a tri gun direct view color CRT, what of CRT based projections ? Few of them even hit 70 degrees deflection but the density of the beam still taxed the poor transistors. But the main problem here is that it was electromagnetic deflection. Oscilloscopes have used electrostatic deflection for longer than I have been alive. There was no problem with geometry much due to long neck lengths but that can be corrected period anyway, a hell of alot easier than it could magnetically.

I was never impressed with projector TVs of any type. The biggest CRT TVs reached 36 inches but they were massive. I recall the cheapest 36 incher by Sony cost €3,000 in the early 2000's. Thus projection TVs were a necessary evil until plasma came along.

quote:


All in all, you go in a TV store and you see lal these different brands (all three of them) and different technlogiers and see a difference in the pictures. But in your own home that does not mean shit. Some people go for the brightest, but I can tell you that color rendition and brightness output are inversely proportional. You can have the bightest thing on the planet, but if it can't reproduce dark (navy) blue, it simply can't. Just like speakers, you can read all the specs you want but you know damnwell not to buy anything until you actually hear them.

I agree, specifications for speakers don't really count for much, unless a manufacturer gives such things as an impedance graph but that would give an idea of sound quality either.

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)

(in reply to Termyn8or)
Profile   Post #: 8
RE: CRT TVs versus Panel TVs - 12/28/2011 10:59:48 PM   
Snort


Posts: 132
Joined: 5/15/2008
Status: offline 		I loved the picture on my old 36 inch Sony CRT, but that thing was HEAVY. Now, I'm happy with my plasma. A CRT that big would need a crane to install...

_____________________________

Not a GT sock. Really.

(in reply to Anaxagoras)
Profile   Post #: 9
RE: CRT TVs versus Panel TVs - 12/28/2011 11:05:42 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline 		"Indeed I am. Nothing wrong with second-hand if it offers the best picture at a small fraction of the price. Many people who spent a lot on a high-end widescreen would care for it. "

Americans are too materialistic for that. They have to hve the newest and the best. Hear the saying "Keep up with the Joneses" ? However in that other post, like I said the 50 Hz problem was worse, and in fact very very few of the CRT based sets here are anything other than 60 Hz.

"the CRT tube to the old fashioned light bulb is my analogy"

An incorrect one. It is still either electrons or ions making a phosphour glow. A light bulb is different. In fact, ions burn up the phophours in a CRT, a problem which was solved a long time ago. However I wonder if that is not the reason why plasma TVs lose their ooomph after so many years. I don't wonder enough to find out though. CRTs were fixed by aluminizing the screen, but before that there was what was called an ion trap. It's up to you if you want to look into it, all I know is if the sonofabitch stops working you have less than a 50/50 chance of getting any of this new junk repaired, at least in the US. Not just plasma either.

http://gadgetbox.msnbc.msn.com/_news/2011/09/23/7926490-vizio-tells-owners-their-sets-are-unrepairable

An excerpt :

"HD Guru came across Jeff Bartran's letter to Vizio CEO and founder William Wang complaining that the company's service department had deemed "unrepairable" his 13-and-a-half-month-old, high-end $1868 Vizio 55-inch LED LCD. Bertran says Wang never responded. "

Read more, the manufacturer recommends simply buying a new one. Fucking junk and these governments let them get away with it. They fill landfills all over the place with nasty shit, seeping into water tables. Wonderful things like inorganioc and unnatural silicon and phosphorous compounds, and up until now, lead in the solder. Many places have "mandated" lead free solder because they know this garbage is on a fast track to the dump, and into the environment. And I can tell you as a professional that lead free solder impedes effective service and decreases reliability. I got witnesses all over the country.

"Not for a tube rectifier."

Maybe back in DeForest's day or something, but not today.

"I was never impressed with projector TVs of any type. The biggest CRT TVs reached 36 inches but they were massive."

I have a 36" projo built in 1988. I have the parts and am going to restore it when I get around to it. When it was new it sat on the shelf alongside a 36" direct view and the pictures were almost identical. In fact the contrast ratio of the RPTV was a bit better because of the way the hybrid lenticular/fresnel screen works. Room light just falls on the green phophours of a direct view, while the screen of a good RPTV diffused it inside the light path onto black surfaces. CRT sometimes had tinted glass and cranked up the current for the same brightness. I've heard from several people that the US is the RPTV capitol of the world, nobody else wanted them. We loved them.

"I agree, specifications for speakers don't really count for much, unless a manufacturer gives such things as an impedance graph but that would give an idea of sound quality either."

Maybe things are different there but here the impedance only matters if you are worried about your solid state amp. They are a constant voltage source, that is the output does not drop due to load like in a tube (valve) amp. Sensitivity is no longer at 1 watt 1 meter, it is 2.83 vots 1 meter.

What's more the method used to measure the frequency response is just about useless since the 1980s. It used to be done with sine waves and a tuned mic which was of course calibrated. Now they use pink noise which is noise with a one third octave bandwidth. The mic is broadband which means it picks up and includes all distortion in the "measured usable" output. That means that when you put in a 60Hz bass note, you can be getting nothing but harmonics, 120, 180, 240 and so forth which will sound like shit. But it's flat within X dB down there. Yes, it has response, just not the proper response. (some are even worse, ANY low note just excites cabinet resonances)

It's just like fucking with the colorimetry of a TV to get a higher brightness output. The red ain't red enough, the blue ain't blue enough and the green ain't green enough. So you crank up the color (difference component) and the damn thing looks like a cartoon. But it specs out really great on "Video Essentials".

You see when I say statistics lie, that doesn't just mean economics and shit like that. ANYBODY will find a way to slew the numbers in their favor, and I have proof positive when it comes to technology.

T^T

(in reply to Anaxagoras)
Profile   Post #: 10
RE: CRT TVs versus Panel TVs - 12/28/2011 11:07:28 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline
quote:

A CRT that big would need a crane to install...


Depending on your neighborhood that could be a good thing. "If you can steal it, you can have it" LOL

T^T

(in reply to Snort)
Profile   Post #: 11
RE: CRT TVs versus Panel TVs - 12/28/2011 11:27:00 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline
quote:

ORIGINAL: Termyn8or
"Indeed I am. Nothing wrong with second-hand if it offers the best picture at a small fraction of the price. Many people who spent a lot on a high-end widescreen would care for it. "

Americans are too materialistic for that. They have to hve the newest and the best. Hear the saying "Keep up with the Joneses" ? However in that other post, like I said the 50 Hz problem was worse, and in fact very very few of the CRT based sets here are anything other than 60 Hz.

You should tell US audiophile enthusiasts that, many will spend $2,000 on a pair of mono QUAD II valve amps from the 1950's. The US has a massive market for specialist stuff.

quote:


"the CRT tube to the old fashioned light bulb is my analogy"

An incorrect one. It is still either electrons or ions making a phosphour glow. A light bulb is different. In fact, ions burn up the phophours in a CRT, a problem which was solved a long time ago.

Termy, a CRT tube is essentially a triode http://www.gizmohighway.com/history/crt.htm - a triode is basically a three element light bulb with a lot of fancy stuff added. Remember this was only a very basic technological equivalence, akin to comparing a plasma with a flourescent tube.

quote:


"Not for a tube rectifier."

Maybe back in DeForest's day or something, but not today.

Read up a bit on rectifier valves (or tubes as you guys call them). In some respects they still outperform the transistor equivalent, hence their use in high performance amplifiers.

quote:


"I agree, specifications for speakers don't really count for much, unless a manufacturer gives such things as an impedance graph but that would give an idea of sound quality either."

Maybe things are different there but here the impedance only matters if you are worried about your solid state amp. They are a constant voltage source, that is the output does not drop due to load like in a tube (valve) amp. Sensitivity is no longer at 1 watt 1 meter, it is 2.83 vots 1 meter.

The impedance does affect performance of transistor amps (speaker-amplifier interaction is pretty complex, and not all tranny amps are born equal - damping factor etc.) but I'm sure you'll agree that it is more a topic for an audio related discussion.

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)

(in reply to Termyn8or)
Profile   Post #: 12
RE: CRT TVs versus Panel TVs - 12/29/2011 1:29:18 AM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline 		"You should tell US audiophile enthusiasts that"

They are NOT in the majority.

"Termy, a CRT tube is essentially a triode"

Oh really. Then find out from that source what kind of triode has a G2, a G3 and a G4. Maybe you can discount G3 and G4 but G2 acts exactly as a screen grid in a tetrode or pentode. Your source is simply wrong. I am not trying to put you down here, but if it has a G2 that acts like a G2 or "screen grid", it is NOT a triode. What's more the way you word it, you make it sound as if light is actually modulated, it is not. It is a focussed beam of electrons which excite the phosphours the same way as in any elecron excited chemical lighting scheme.

"Read up a bit on rectifier valves (or tubes as you guys call them). "

Did that when I was ten years old. I have well over thirty years experience in the field and have proven alot of people wrong, like manufacturer's reps, engineers and so forth. My qualifications are quite bona fide to say the least. I have designed and built audio amps as well as highly specialized test jigs for specialized applications. I have reengineered more things than most people have owned, mainly because I did it at work. No offense taken, there is no way for you to know that. But you are not going to prove me wrong. Not about this shit.

"The impedance does affect performance of transistor amps (speaker-amplifier interaction is pretty complex, and not all tranny amps are born equal - damping factor etc.) but I'm sure you'll agree that it is more a topic for an audio related discussion. "

Start one. Start by reading things by Roy Allison, Bob Carver etc. Forget Bose, Dr. Bose is admittedly a smoke and mirrors guy, and is known as such by the few audiophiles here. He is known for being able to get the best sound from the cheapest drivers actually, when it comes to the lower end. If not for the 901s and the Acoustimass his shit would be selling at Walmart.

His ideology differs from mine, he is all about exciting waves, I am about brute force. And yes that does involve the damping factor, formerly referred to as the dampering factor. If you want to kniow how speaker impedance affects valve amps as opposed to solid state amps I can tell you, but suffice it to say, the lower the damping factor of a solid state amp the more it behaves like a valve amp. Most valve amps are lucky to have a damping factor of 2, for the best response in a voltage based system (modern) damping factors should run at least 50. That means it actually has an output impedance of 0.16 ohms if dealing with an eight ohm speaker.

To understand the actuall acoustic effect do this little experiment. Take a woofer, the larger the better, and a good one. Move the cone with your hand being careful not to dent the dust cover. Move it a few times and get an idea how much force it takes. Then take something and short out the terminals. Notice the difference. It's as if you put a (car/hydraulic) shock absorber on it. Hydraulic is THE REASON it's called dampered, or damped. Some high end arms for turntables actually had reservoirs of oil and paddles attached to it to keep them stable, just like the shock absorbers in your car.

The tube amp can supply alot of voltage, ergo power of course, but with the low output impedance a well designed solid state amp FORCES the cone into position. It is now seen as a must for true high fidelity except for the most eccentric. And if you think normal audiophiles are rare......................

Start an audio thread if you feel like it. I can tell you alot about equalization, cabinet design, room acoustics, the differences between speaker types and all that. I have been in the field for a very long time. I was the AV dude. Now of course I don't really care except for my own shit. It works, gimme the money see ya later. After I've sat there with a spectrum analyser and setup the room for some idiot then he says "I like to see a nice smile on the equalizer"....... Lucky I didn't have a big fucking hammer in my toolbox.

Myself, my speakers do not need any equalization.

T^T

(in reply to Anaxagoras)
Profile   Post #: 13
RE: CRT TVs versus Panel TVs - 12/29/2011 4:28:04 AM   
FrostedFlake


Posts: 3084
Joined: 3/4/2009
From: Centralia, Washington
Status: offline 		Lotta ground been covered. I would like to add three thoughts.

1/ The mid-priced Philips 32" LCD (1080p) unit MAY be faulty.

2/ When selecting a new display, you MUST observe the unit, same make, model, product number, in action before you buy. This, to determin if the screen finish is glossy or flat. A glossy screen might seem better, because it is shiny. But, it is in fact inferior, because it is shiny. A glossy screen reflects light well. This pollutes the picture with room light, making it difficult to see. A flat screen does not reflect light well, so you can see the picture much better.

3/ Do not overlook the idea of using a projector. This is the only way to go if you want a 7+ foot screen. If you happen to have a blank wall that will serve as a screen and can control room lighting sufficiently, yer golden. Otherwise, make a frame out of PVC tube, stretch a sheet over it, bring the frame from the garage and hang it from the ceiling when it is showtime, and yer golden.


_____________________________

Frosted Flake
simul justus et peccator
Einen Liebhaber, und halten Sie die Schraube

"... evil (and hilarious) !!" Hlen5

(in reply to Termyn8or)
Profile   Post #: 14
RE: CRT TVs versus Panel TVs - 12/29/2011 4:59:45 AM   
PeonForHer


Posts: 19612
Joined: 9/27/2008
Status: offline
quote:

ORIGINAL: FrostedFlake
Do not overlook the idea of using a projector.


You can just put a magnifying glass in front of your standard telly. Hold a bit of paper in the other hand - presto: TV image projected onto bit of paper.

_____________________________

http://www.domme-chronicles.com


(in reply to FrostedFlake)
Profile   Post #: 15
RE: CRT TVs versus Panel TVs - 12/29/2011 7:29:02 AM   
ashjor911


Posts: 7793
Joined: 9/7/2010
From: balcony, having a Smoke
Status: offline 		throu the fillips with the garbage, get one of the LCD from "Sony or samsung" & you will find the differance..
a Plasma screen, "from how i understand it its a living cells which can die after some time. & its price is way to high.

CTR: they used to have a very small CPU & GPU chip compined together from Sony.
LCD: have that same CPU chip from the brand of the LCDTV & the GPU from Sony "that what makes it slow"
LCD: "for samsung have a contraposition 1:500.000"


now, almost 70% of the LCD TV have almost 70% of the TV from Samsung
"samsung did buy the half of sony for LCD Corp. 2 days ago"

then i have to ask you thins.
why did you buy Philips, when you can buy the Samsung ... the source?


_____________________________

"operative" working undercover for the federal government of bangladesh.

my name is : bonsh ... jamesh bonsh.
code name : 009.5
licensed to give formla

(in reply to Anaxagoras)
Profile   Post #: 16
RE: CRT TVs versus Panel TVs - 12/29/2011 7:37:37 AM   
LaTigresse


Posts: 26123
Joined: 1/15/2006
Status: offline 		I don't know anything about all of the technical hooey up there but I do know that the television I got for Christmas last year still rocks as much this year. People come over and drool over it. I drool over it when I watch a DVD I haven't watched in a long time. The colour is amazing and even though it's not 3D.......some things almost look 3D. When I go downstairs and try to watch something on the old Samsung I bought 15 years ago........I cannot believe the difference.

_____________________________

My twisted, self deprecating, sense of humour, finds alot to laugh about, in your lack of one!

Just because you are well educated, articulate, and can use big, fancy words, properly........does not mean you are right!

(in reply to ashjor911)
Profile   Post #: 17
RE: CRT TVs versus Panel TVs - 12/29/2011 12:57:03 PM   
Anaxagoras


Posts: 3086
Joined: 5/9/2009
From: Eire
Status: offline
quote:

ORIGINAL: Termyn8or
"You should tell US audiophile enthusiasts that"

They are NOT in the majority.

Obviously they are not in a majority but there is a bigger US enthusiast market (not just in audiophilia) than in any other part of the world. That sundermines your assertion that people in the US are just crass materialists in contrast to the rest of the world

quote:


"Termy, a CRT tube is essentially a triode"

Oh really. Then find out from that source what kind of triode has a G2, a G3 and a G4. Maybe you can discount G3 and G4 but G2 acts exactly as a screen grid in a tetrode or pentode. Your source is simply wrong. I am not trying to put you down here, but if it has a G2 that acts like a G2 or "screen grid", it is NOT a triode. What's more the way you word it, you make it sound as if light is actually modulated, it is not. It is a focussed beam of electrons which excite the phosphours the same way as in any elecron excited chemical lighting scheme.

There are variations in CRT design between conventional tubes and CRTs but the basics of a CRT relate to a triode behaviour http://en.wikipedia.org/wiki/Cathode_ray_tube#Gamma but even if a CRT is more properly described as a pentode or a tetrode, the technological link with the traditional light bulb is still strong since all these technologies come from the same source. A tetrode is just a triode with a screen grid and a pentode is just a tetrode with a suppressor grid.

Termy, it sounds like you are reading too much into what I said to win an argument that never existed in the first place. Again I say I did not say they were the same but that the technologies were derived from the same source so have some parallels. Obviously there would be huge differences as well since bulbs aren't used to reproduce video images!

quote:


"Read up a bit on rectifier valves (or tubes as you guys call them). "

Did that when I was ten years old. I have well over thirty years experience in the field and have proven alot of people wrong, like manufacturer's reps, engineers and so forth. My qualifications are quite bona fide to say the least. I have designed and built audio amps as well as highly specialized test jigs for specialized applications. I have reengineered more things than most people have owned, mainly because I did it at work. No offense taken, there is no way for you to know that. But you are not going to prove me wrong. Not about this shit.

Termy, you've gone on and on about your qualifications in the past but were still wrong for example about very basic stuff like refresh rates being the same as frames per second. Having thirty years experience as a repair man is great and you should be proud of that but it doesn't make you the Edison of the late 20th Century. Besides which, when you were around (from the early 80's) you wouldn't have dealt much at all with rectifier valves. You would know that rectifier tubes last a very very long time in properly designed circuits.

quote:


"The impedance does affect performance of transistor amps (speaker-amplifier interaction is pretty complex, and not all tranny amps are born equal - damping factor etc.) but I'm sure you'll agree that it is more a topic for an audio related discussion. "

Start one. Start by reading things by Roy Allison, Bob Carver etc. Forget Bose, Dr. Bose is admittedly a smoke and mirrors guy, and is known as such by the few audiophiles here. He is known for being able to get the best sound from the cheapest drivers actually, when it comes to the lower end. If not for the 901s and the Acoustimass his shit would be selling at Walmart.

His ideology differs from mine, he is all about exciting waves, I am about brute force. And yes that does involve the damping factor, formerly referred to as the dampering factor. If you want to kniow how speaker impedance affects valve amps as opposed to solid state amps I can tell you, but suffice it to say, the lower the damping factor of a solid state amp the more it behaves like a valve amp. Most valve amps are lucky to have a damping factor of 2, for the best response in a voltage based system (modern) damping factors should run at least 50. That means it actually has an output impedance of 0.16 ohms if dealing with an eight ohm speaker.

To understand the actuall acoustic effect do this little experiment. Take a woofer, the larger the better, and a good one. Move the cone with your hand being careful not to dent the dust cover. Move it a few times and get an idea how much force it takes. Then take something and short out the terminals. Notice the difference. It's as if you put a (car/hydraulic) shock absorber on it. Hydraulic is THE REASON it's called dampered, or damped. Some high end arms for turntables actually had reservoirs of oil and paddles attached to it to keep them stable, just like the shock absorbers in your car.

The tube amp can supply alot of voltage, ergo power of course, but with the low output impedance a well designed solid state amp FORCES the cone into position. It is now seen as a must for true high fidelity except for the most eccentric. And if you think normal audiophiles are rare......................

Start an audio thread if you feel like it. I can tell you alot about equalization, cabinet design, room acoustics, the differences between speaker types and all that. I have been in the field for a very long time. I was the AV dude. Now of course I don't really care except for my own shit. It works, gimme the money see ya later. After I've sat there with a spectrum analyser and setup the room for some idiot then he says "I like to see a nice smile on the equalizer"....... Lucky I didn't have a big fucking hammer in my toolbox.

Termy I asked you to take that topic to another thread as this is about something very different. Rambling about technical stuff unrelated may well disrupt a different topic.

Valve amps are not lucky to have a damping factor of two. That would only relate to zero feedback amps which have a high output impedance. It all depends on the design, the interraction of the valves to the output transformer, and levels of negative feedback used. I know a fair bit about audio technology but don't boast. I agree Bose is crap though.

< Message edited by Anaxagoras -- 12/29/2011 12:58:06 PM >

_____________________________

"That woman, as nature has created her, and man at present is educating her, is man's enemy. She can only be his slave or his despot, but never his companion." (Venus in Furs)

(in reply to Termyn8or)
Profile   Post #: 18
RE: CRT TVs versus Panel TVs - 12/29/2011 1:21:30 PM   
PeonForHer


Posts: 19612
Joined: 9/27/2008
Status: offline 		CRT tellies are for pansies, Anax.

_____________________________

http://www.domme-chronicles.com


(in reply to Anaxagoras)
Profile   Post #: 19
RE: CRT TVs versus Panel TVs - 12/29/2011 1:30:42 PM   
Termyn8or


Posts: 18681
Joined: 11/12/2005
Status: offline
quote:

A tetrode is just a triode with a screen grid and a pentode is just a tetrode with a suppressor grid.


Fine, they're all triodes with extra grids LOL.

The CRT guns are a four element device, also known as a tetrode at the very least. There is a cathode, then a control grid. Making the control grid less negative with respect to the cathode increases current. Similarly making the second grid more positive with respect to the cathode increases current. You might enjoy contacting those erroneous sources and correcting them, maybe I'll take care of wiki after I have a look.

At the second grid is where all this ends though. the next element is the focus electrde, some refer to it as an anode or "first" anode but I consider that erroneous because it does not pass current. It's only functuion is to constrict the beam into a,,,, well a beam. Then the ultor, or second anode is actually the plate. That is where the current must be supplied at a high voltage.

The CRT is actually more efficient than an incandescent lamp. I believe I mentioned that quite a bit of power is used by the deflection circuits, and actually without them the CRT would be the most efficient by far of any of the current technologies.

But going into a skid here to get back on topic...........

The problem with CRTs is that the phosphours are not black. Therefore to get contrast it requires more brightness. Over the years they have improved things by tinting the glass, and in some cases even the phosphorurs themselves. That's right, the red phosphour is not white with a red dye, it is phosporous doped to produce that particular frequency of light.

Since a direct view LCD is backlit and black is produced by blocking light, obviously better contrast can be achieved. The technology has gotten better over the years as well and in the last few using LED backlighting has saved watts and money, which will trickle down to the consumer price as soon as the manufacturers have enough money (LOL).

I think plasma is dead. I heard something about the gas deteriorating over time which - who knows. However long that takes there is also the factor of the phosphours wearing out. This happens in CRTs as well. Even without ions, they has a finite life.

This is not true of the LCD. What happens to the LCD sets barring a backlight failure is usually a defect developing in the panel itself, (which is NOT wearing out) or a fault in the processing circuitry.

I'm probably cutting my own throat here but when these things break half the time just throw them out. The deal is this, if it does NOTHING or has NOTHING at all on the screen you might want to have a shop look at it. There will be a charge for this, some places charge as high as $80 in the US due to the complexity and cost of parts. If you DO have something on the screen but it is fucked up you are better off canning it. Either that or you could make a deal with a shop that if they can't fix it for what you are willing to pay they just keep it, but that opens the door to abuse.

Basically there are two types of sets to avoid. Not at all cost but they are a bit less desirable. Plasmas and LCD based projection TVs. Other than that it doesn't much matter. Get the longest extended warranty you can and save the box.

T^T

ETA : Now was the latter part of that on topic enough ?

< Message edited by Termyn8or -- 12/29/2011 1:32:54 PM >

(in reply to Anaxagoras)
Profile   Post #: 20
Page:   [1] 2   next >   >>
All Forums >> [Casual Banter] >> Off the Grid >> CRT TVs versus Panel TVs Page: [1] 2   next >   >>
Jump to:





New Messages No New Messages
Hot Topic w/ New Messages Hot Topic w/o New Messages
Locked w/ New Messages Locked w/o New Messages
 Post New Thread
 Reply to Message
 Post New Poll
 Submit Vote
 Delete My Own Post
 Delete My Own Thread
 Rate Posts




Collarchat.com © 2025
Terms of Service Privacy Policy Spam Policy

0.141