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People Who Hunt Down Old TVs

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Re: People Who Hunt Down Old TVs

#81

Post by mrandish »

0x445442 wrote: post #59
speeder wrote: post #52

Earlier quoted context omitted.

I had a music teacher that insisted analog recordings were different. One day she said there is a simple way to prove it. Certain stringed instruments have the string move on their own to the correct note if you put them near a source of similar sound. If you put these instruments in front of a speaker playing from an analog source and have the strings move, then play the exact same music but from a digital source on…

I find this dubious since the effect she was describing is caused by resonance frequency. Since, in the example provided, the source is an amplified speaker pushing air in both cases the outcome should be the same. The more famous test of this principle is the breaking of a glass and I would be surprised if this hadn't been done with digital signal inputs.

> I find this dubious

I agree. In both cases a continuously varying voltage is driving speaker cone deflection. If the voltages of two different signals vary in precisely the same way, the cone will deflect to exactly the same degree and the resulting pressure wave will generate the same resonant response from any surface it encounters. When properly implemented, today's high-end, esoteric ADC and DAC converters have insane bandwidth, frequency response and fidelity far exceeding these requirements.

Some of the confusion comes from the fact that back when consumer audio transitioned to digital and these production workflows were new, some early digital recordings were incorrectly engineered or mastered creating artifacts such as aliasing which critical listeners could hear. Some people assumed the artifacts they heard were innate to all digital audio instead of just incorrect implementation of a new technology. Even today, it's possible to screw up the fidelity of a digital master but it's rarely an issue because workflows are standardized and modern tooling has default presets based on well-validated audio science (for example: https://en.wikipedia.org/wiki/Noise_shaping#Dithering). But even in the analog era it was always a truism in audio and video engineering that "there are infinite ways to screw up a signal but only a few ways to preserve it." And it remains true today. To me, one of the best things about modern digital tooling is it's much easier to verify correctness in the signal chain.

Re: People Who Hunt Down Old TVs

#82

Post by WalterBright »

alnwlsn wrote: post #60
WalterBright wrote: post #37

Those aren't old TVs. When I was a kid, I'd go to the TV repair shops and take old "unrepairable" vacuum tube TVs (no transistors!) off their hands. At home I tried to fix them. I had no idea how to fix them. But I had a lot of fun trying. One of the fun things was to randomly swap around the vacuum tubes and see what would happen. Very entertaining! I used to have a box full of scavenged tubes. Sadly, I eventually t…

Your mom was probably thinking along the right lines haha. But don't worry, TV tubes are practically worthless. I've been to swap meets for an antique radio club in my area. Sometimes, there will be a few boxes of tubes from TV sets there (400-500 tubes) and people literally can't give them away. Tubes from audio equipment are the only ones people are after.

Thanks! I didn't know that.

Re: People Who Hunt Down Old TVs

#83

Post by WalterBright »

voldacar wrote: post #43
WalterBright wrote: post #37

Those aren't old TVs. When I was a kid, I'd go to the TV repair shops and take old "unrepairable" vacuum tube TVs (no transistors!) off their hands. At home I tried to fix them. I had no idea how to fix them. But I had a lot of fun trying. One of the fun things was to randomly swap around the vacuum tubes and see what would happen. Very entertaining! I used to have a box full of scavenged tubes. Sadly, I eventually t…

Most TV tubes aren't too valuable. Now if your TV was made by telefunken, that might be a different story

I do prefer tubes that have the funk.

Re: People Who Hunt Down Old TVs

#84

Post by cyrialize »

When I used to run super smash brothers melee tournaments in my old apartment basement I had 4 CRTs.

I still have one tiny CRT, the size of the screen is very small - roughly a banana from corner to corner.

CRTs are absolutely required for in person melee tournaments. Playing not on CRTs introduces input lag of a few frames.

There are 60 frames in a second in melee - so it's roughly one frame per millisecond.

You may not think that is that big of a deal - but when a specific move has a 4-7 frame window, input lag becomes a problem.

If you ever watch a melee tournament on YouTube or in person, you will either see CRTs everywhere, or computers emulating melee.

When emulated there isn't input lag. The lag comes from the conversion needed to display melee on a non CRT TV I believe.

Re: People Who Hunt Down Old TVs

#85

Post by Dylan16807 »

sokoloff wrote: post #55
Dylan16807 wrote: post #46

Earlier quoted context omitted.

> The switch to LCDs/LEDs was in a lot of ways a step back. Sure, we don't have huge 40lb boxes on our desks, but we lost the ultra-fast refresh rate enabled by the electron beam, not to mention the internal glow that made computers magical (maybe I'm just an old fuddy-duddy, like people in the 80s who swore that vinyl records "sounded better"). CRTs don't have particularly good refresh rates. There is very little de…

The heated filament in many old CRTs would glow orange.

Okay, then that was already pretty much gone by the time we switched to LCD.

Re: People Who Hunt Down Old TVs

#86

Post by imcritic »

thworp wrote: post #76
emh68 wrote: post #15

Sometimes I think about the bizarre path computer technology took. For instance, long-term storage. It would stand to reason that we'd invent some kind of big electrical array, and that's the best we could hope for. But hard drive technology (which relies on crazy materials technology for the platter and magnets, crazy high-precision encoders, and crazy physics like floating a tiny spring over the air bubble created…

Imo OLED has completely eclipsed CRT by now. I don't know enough to say where CRTs could be today if they had gotten the development $ that went into other tech. But to be as good as OLEDs they would have had to find something else than phosphor as the inner coating. For response times, CRT will always remain the king of dark-to-light response times, but afterglow for bright-to-dark would always be a factor unless a…

Ghosting from long display of static image is real.

Re: People Who Hunt Down Old TVs

#87

Post by mrandish »

ThrowawayTestr wrote: post #36
mrandish wrote: post #30

Earlier quoted context omitted.

> like people in the 80s who swore that vinyl records "sounded better" I'm not one of those people who ever thought vinyl sounded better than a properly recorded and mastered digital version and I've always believed a high-bandwidth digital audio signal chain can recreate the "warmth" and other artifacts of tube compressors well beyond the threshold of human perception, however a broadcast-quality, high-definition CR…

Have you looked at any high end OLEDs lately?

Yes, my background is in broadcast video engineering. An edit suite I'm in regularly has a $10,000 24-inch BVM-E251 reference monitor for color grading. At home I have a $4,000 LG C5 OLED. My dedicated home theater room is based around a $12,000 4k laser projector. I also own a Sony BVM series broadcast CRT, various Trinitrons CRTs and a retro gaming arcade cabinet built around a 25-inch analog RGB industrial CRT (Wells Gardner D9200). I use an optical colorimeter for display calibration.

All of these displays are unique tools each with differing capabilities. I own and use them all for what they are best at. Flat panel technologies can produce incredible visuals with certain strengths no CRT can replicate (when properly calibrated and given a high-quality source signal). However, the reverse is also true, extremely high-end cathode ray technology, with an appropriately high definition dot/shadow mask and phosphors, can generate visuals with traits no current flat panel display technology can duplicate. To be clear, I'm not talking about any CRT consumer television you've ever seen. A decent OLED display of today can look far better than even the best 1990s televisions, but consumer televisions were standard definition and hard-limited to less than 6 MHz of signal bandwidth (usually much less), so any comparison between the fundamental display technologies ('cathode ray-irradiated phosphors' vs 'light emitting diodes') is meaningless if not evaluated with the same resolution and bandwidth input signal. And you've never seen a high-definition CRT like a KW-3600HD fed with a 30 MHz HD source signal. But they exist and I've seen one.

Everything in display engineering involves trade-offs. CRTs and light emitting diodes are based on different materials with fundamentally different optical properties and underlying physics. Each has their own unique strengths. Neither can fully replicate the entire range of the other in every respect. This is not a personal aesthetic opinion, it's a carefully qualified technical assessment based on objective measurement and it's consistent with the physical capabilities of the respective technologies.

Re: People Who Hunt Down Old TVs

#88

Post by estimator7292 »

everdrive wrote: post #68
Aurornis wrote: post #66

Earlier quoted context omitted.

> all sorts of anti-aliasing, lighting, etc, and a resolution race that can only be described as pathological I enjoy CRT nostalgia now and then, but modern high resolution games are absolutely amazing. The blurry, low resolution, low refresh rate CRT look is fun for old games, but playing in 4K at 100+ fps on a modern monitor is an amazing experience on its own.

They're blurry in brand new ways due to how sloppy AI upscaling is.

There's also that godawful temporal shader or whatever that leaves black outlines drifting behind moving objects. I honestly cannot fathom why anyone would willingly use that effect, it straight up looks like a render error.
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