Topping LCD Display Degradation Over Time - Study: A70 Pro

[mike7877]

I bought my A70 Pro in March 28 of 2024 and a D70 Pro Sabre May 9 2024. On July 20 2024

March 28, 2024 - A70 Pro
May 9, 2024 - D70 Pro Sabre
July 20, 2024 - D90 III Sabre

So the A70 Pro and D70 Pro Sabre were used together for about 2.5 months, on about 50% of the time. I used the D70 Pro Sabre elsewhere for 3 months on 24/7

So the D70 Pro Sabre has about 4.5 months of 24/7 use, or 3,240 hours.

My A70 pro has that same 50% of 2.5 months (call it 50% of 3 like the Sabre got), and that's 1,080 hours

Since July 20, 2024, my A70 Pro has been on an average of 16 hours per day which is 7,200 hours. Add that 7,200 to 1,080, and that's about 8.4K hours.

In the picture below from the top down it goes
- Brand New A70 Pro: 0 hours
- 15mo. old A70 Pro: 8,400 hours
- 13mo. old D70 Pro: 3,200 hours

I took the picture with no processing and static ISO/exposure - the brightness and colour temperature reflects reality very well if you've got a calibrated display

The A70 Pro (headphone amp) runs a couple degrees warmer than the DACs, not usually more than 5C (in my use anyway. High power with low impedance cans might be different)

If that's too big, here:

When I first compared the A70 Pro's display to the D70 Pro Sabre's, I was thinking to myself "...are these different LCDs? ...these look like different LCDs... But the colour - it's so similar! There's a slight difference in tint... The real difference, though - the thing which initially caught my eye, was the phase of the light. If you've ever put a solid colour on an LCD and looked at it from off angles, that shift is phase. I noticed that the phase shift on the mostly black background was different between the displays. It was significant - at first I thought the display was square and was installed 90 degrees different in the devices. Nope! Just different... Now you can tell there's a clear difference in brightness, and the center (A70 Pro) is cooler.

I don't know what can be done from this... I went with medium brightness so that in the future I could increase medium to high when the light wore down, but it looks like I should have gone with "low".

It's too bad there's not an "off" position. And it's too bad when you select Auto and the screen times out (and goes black), the backlight is left on for this...

I guess from here on out, this is the display colour shift and dimming that you can expect after 10,000 hours on medium brightness. I wish it was better. I wonder if there's just no way to power down the LCD with the firmware, or if that's a feature that can be added.


I'm probably in a fairly unique situation to show this - I assume most people with the A70 Pro, if they have another Topping DAC with this display, will be using the DAC and A70 Pro at the same time, so the screens will degrade together, gradually shifting over time... In any case, has anyone else noticed this? And am I crazy for having my A70 Pro powered on for over 8k hours over the past 15 months? No, something is not always going through it, but it is my PC sound when I'm using my PC, and it does my headphones for everything I use headphones for, and it's also my preamplifier for my 2.0/2.2 system.. If anyone's wondering about potential error, I'd say likely up to 10% on each number, definitely no higher than 20% on any number

 

[Saponetto]

My first thought is: Are you supposing that some display drive resistors got thermally cooked/alterated in value?
This was something quite frequent with old, beautiful fluorescent displays, as far as I can remember.

 

[lucian]

was it staying in the sun?

 

[markstein]

Are these LCDs or OLEDs?

 

[Sokel]

Up until a year ago or so, I was asking the type of display at every new review.
I know nothing about them except I see so many of them degraded (some at an unreadable state) in fairly short times.

Which ones are really immune to this?

 

[markstein]

Well, I personally would not want a device with OLED display which is permanently switched on. My old MiniDSP SHD had an auto switch-off option, that can be a workaround.

 

[mike7877]

My first thought is: Are you supposing that some display drive resistors got thermally cooked/alterated in value?
This was something quite frequent with old, beautiful fluorescent displays, as far as I can remember.

No, I was just ruling out temperature as having much effect there

 

[mike7877]

was it staying in the sun?

No, it's never seen direct sun and it's not in a bright room (at any time of day)

 

[mike7877]

Are these LCDs or OLEDs?

These are LCDs. The colour shifting so obviously to blue is kind of something I'd expect more from an OLED to do this quick, but apparently, LCD too. The LED backlight is probably yellow phosphor on blue, and the yellow phosphor is dying more quickly. Brightness is going down too, which means it's not just the phosphor that's defective or low quality. You can see that even the D70 Pro Sabre with its relatively low usage vs the A70 Pro, when compared to the brand new A70 Pro, though the colours are still mostly good, D70 Pro Sabre is still fading in brightness

 

[mike7877]

Up until a year ago or so, I was asking the type of display at every new review.
I know nothing about them except I see so many of them degraded (some at an unreadable state) in fairly short times.

Which ones are really immune to this?

I dunno... I expected more better at 8k hours than this, though... I expect degradation to continue at about the same rate, maybe accelerating slightly. So at 20k hours it'll be 300% (vs 100% now). At 40k hours it'll be 800% (vs. 100 now). Going from Med to Low brightness might make 225% at 20k and 650% at 40k hours. I'm not looking forward to that...

 

[mike7877]

Well, I personally would not want a device with OLED display which is permanently switched on. My old MiniDSP SHD had an auto switch-off option, that can be a workaround.

With OLEDs it's OK if they're permanently switched on, just as long as they're not displaying anything. I have an OLED TV which for reasons has been on for 42K hours since it was bought, average type of things you'd expect on a TV, mostly SDR with brightness (peak white) average of 225-250 nits. There has only been a slight cooling of the colour temperature, maybe 150K, which I easily fixed in the service menu. A good OLED can last a long long long time. My TV is doing much better than I thought it would.. Now it's getting into "board breaking" territory...
Hopefully all the caps Sony used were good. It's also out of the sun and I don't watch cartoon type stuff on it (bright saturated colours taking up 100% of the screen), so average power to the panel stays around 40-60 watts, with 60 watts powering the electronics (kill-a-watt bounces between 85 and 140W, usually around 105. Only commercials will occasionally show a full screen of yellow or something, causing an outrageous 430 watt draw from the wall for 10 seconds...

 

[Zekbone]

While OLED burnin is a reasonable concern, the fact of the matter is that LCD backlights aren't really that much more durable. They're just usually easier to repair. RTINGS actually found that certain types of LCDs failed earlier than OLED. https://www.rtings.com/tv/tests/longevity-burn-in-test-updates-and-results

 

[wwenze]

Degraded or just different from the beginning

 

[mike7877]

Degraded or just different from the beginning

I'll treat your ambiguously formed sentence as a question, and assume you didn't read the OP... Did you not see the OP? I explained in detail... It's at the top
I also have a pic somewhere on my phone of the first A70 Pro + the D70 Pro sabre running with nearly the same hours, and they look very close to identical in it ..
.
Since this drift didn't take too long, I'm sure other people who leave their stuff on might have noticed the hue changing. If you're them, you can compare the hue of the online pictures from Topping's website to the hue of your unit if you use a flagship phone or Surface tablet/Laptop or iPad or MBP, anything with a calibrated display - your unit should be very close to the picture. I've had 4 units, one went back because I didn't want to keep it (D70 Pro Octo went back - the Sabre was better to me). When I had all 3, the 3 displays' colour matched each other and the online pics 99.x% (through calibrated displays, ofcourse)), and now with my second A70 Pro, running alongside the least used device with same installed display (the DAC, or D70 Pro Sabre), they are very close in colour - brightness is the much more significant different (even though the colour temperature is eveerrr so slightly cooler on the DAC)

 

[mike7877]

While OLED burnin is a reasonable concern, the fact of the matter is that LCD backlights aren't really that much more durable. They're just usually easier to repair. RTINGS actually found that certain types of LCDs failed earlier than OLED. https://www.rtings.com/tv/tests/longevity-burn-in-test-updates-and-results

That.... that....... that...................................

I'm appalled!
After a quick look, LCDs seem WORSE than OLEDs!

And it wasn't like this in years past..... I don't know with WHAT processes they're making these TVs... Is it the quality of the raw materials??? Or is this how things have to look so that they'll be broken between year 2-5...?

This is just disgusting... These TVs look like they've been physically beaten! And when it's not the TFT, it's the backlights! How much do those single LEDs they use to shine behind the LCD cost? They're 25c a piece, and they use what... 50 of them? Well how about you use 200 of them and 5-6x the backlight longevity? Also there will be less colour drift over time! People won't need to recalibrate on a 2-3 month basis....

For those who didn't look... Here's a preview after about half a year on! I don't know the details, but even full brightness this shouldn't happen after 2 years - it shouldn't happen EVER!

2 years... less than 20,000 hours, and this is what the dang TVs are looking like!

.................

OK, so it looks like 22 months is where failures start increasing rapidly for a lot of modern TVs. So you can expect 5-10K hours of good performance, and then things go to $#!T

What is wrongggg with this world? No wonder 8K hours there's obvious colour change...


If TV manufacturers would just make LCDs the way they used to, they'd work for over 100K hours. When you, as an engineer, see LED colour shift over time with use and at various temperatures, what you're supposed to do is work out how many you need so that you don't lose brightness or have noticeable colour shift for 40-60K hours... If that means you need 500x 25C lights (cheaper in bulk), or you need to spend $100 to light up the back instead of $20 for your $1500 TV, you spend that 80 bucks... If you, as a greedy business owner just haaaaave to have a 200% markup on all your TVs, add 200% of that 80 bucks to the final sale price! We consumers will pay 10% more for something that isn't going to start looking off IN THE FIRST DANG YEAR.


It's literally infuriating seeing how horrible LCD TVs are performing. Some of those are expensive, too! Doesn't seem to make a difference... I almost bought one of them instead of my Sony A8G OLED! That would've been catastrophic, I see...

 

[Zekbone]

snip

I'm personally not worried for my own TVs and Monitors, but I share your frustration. My own 42 inch LG C4 i use as a PC monitor and desktop theater is coming up to 2400 hours of usage after a year. I keep it at 100 nits (33 on OLED brightness setting according to RTINGS) which feels very nice and comfortable and is technically the most accurate. Or maybe that's just copium to keep my 900 dollar purchase from burning in.

 

[mike7877]

I'm personally not worried for my own TVs and Monitors, but I share your frustration. My own 42 inch LG C4 i use as a PC monitor and desktop theater is coming up to 2400 hours of usage after a year. I keep it at 100 nits (33 on OLED brightness setting according to RTINGS) which feels very nice and comfortable and is technically the most accurate. Or maybe that's just copium to keep my 900 dollar purchase from burning in.

I've got 42,000 on my Sony A8G (2019, standard panel)

I was really interested in OLEDs from 2019 through 2021, so read all I could and did some deep thinking. What I've come to conclude is 2019 panels will probably prove to be the most durable of the standard panels (everything 2017 through 2021, and LG A/B/and I believe C after 2021).

If 2019 is 100%, 2018 will be 90%, and 2017 will be 60-70% due to early red
subpixel fade. 2020 and 2021 will probably be 80%, and 2022 onwards will probably be 60-80%. These aren't absolute longevity numbers, this is my estimation for panel resilience. TV resilience will probably be about the same due to "optimization" (ie. localized dimming of static elements, image shift etc etc. will roughly equalize the cost saving measures, in..most, circumstances....)

So at 42,000 hours, my A8G has lost 3-5% brightness on all subpixels, with red losing 1-2% more than B/G/W (not a problem, I fixed this in the service menu at 20 or 25k, and soon it will be time for another 1-2% red subpixel boost (no, my TV's not digitally calibrated, but I've got it very close to my calibrated SDR LCDs)).

I've done a few thousand hours of PC use - advice for you:

- make your desktop background a saturated but dark colour, using mostly blue with a bit of green. Blue and green last longest and create the least amount of heat. Also it's unobtrusive.

- auto hide your taskbar. Periodically rearrange any bright system tray icons, especially the red, orange, yellow ones. Also rearrange the default position of your pinned programs about as often

- never maximize your windows, especially ones you have open a lot. It's best to sacrifice a little bit of space than to wreck the edges... You can span the entire width and extend to the bottom (in programs without a status bar spanning their bottom edge), you just need to focus on the file menu/min max exit butons/title area - nothing worse than a dim top right corner from that dang redx

- You have about 1000-1500 hours before bright HUD elements displayed at ~200 nits will start appearing on full grey screens. It's best to adjust the size of the HUD every 300-500 hours, and if you can move stuff around, once you've adjusted the size 4-5 times, rearrange and then go through sizes of that arrangement. If you don't need every drop of performance from your GPU, games in windowed mode and shrunk to 80-95% and put placed randomly every time is good.

every month or two you should do various full colour slides at different saturation. Your display is basically new right now - make 5% grey, red, green, blue, 10%, 25%, and 50%. Display them at 100 nits and know what they look like. If you ever start seeing an element burning in, don't worry, you've caught it in time - you might get a few spots over the course of the lifetime of the display - doesn't matter. As long as they're few and far between and small and not severe, you'll never notice them except as you catch the mistakes which caused them.

If you really want your display to last a long time, get a couple 120mm fans and direct their airflow through the black plastic area behind the panel which contains the electronics. The OLED display will be 7-12 deg C hotter where there is plastic electronics box behind, unless you keep a small amount of air moving through. You can use cardboard and duct tape and a USB port to fan input cable to a splitter. 5V to a 12V 120mm 1800RPM fan will probably spin at around 500RPM: nearly silent and more than fast enough to keep your entire panel at the same temperature +-2 deg C. Why does this matter? Well, often a 10-15 deg C reduction in operating temperature of a solid state device equals a doubling of its lifespan. You don't want the bottom centre of your prized OLED to dim and blue faster than the rest of it... I read of someone who watched anime and cartoons a lot, and after 10-15k hours, the simpsons looked green in the middle and stayed yellow around the top/side edges. Anime and cartoons often have the TV pulling a lot more power than usual though. Normal SDR and HDR movies will average less than 50 watts to the panel for the duration, while, depending on how saturated the colours are, even at low to medium brightness, 200 watts can easily be the average, with peaks over 400 watts. Personally, I was going to run fans through mine, but it got to 10k hours, then I was like "it's too late", and now it's at >40k hours and there's only now just the slightest difference able to be noted.

-If you have white at ~80-150 nits across the whole screen for, say, web browsing, you might notice that, temporarily, where the back of the panel is covered in electronics, after 10 minutes or so, will look 5-8% brighter + have a slightly blueish tint vs the uncovered area. The fan will fix this!

With a fan and the tips above, as long as your control/power boards don't go, you should be able to get >30K hours from your C4. Oh, also avoid firmware updates if they have them. It's a display, if LG has a bad quarter or is sitting on too much inventory

 

[Zekbone]

I've got 42,000 on my Sony A8G (2019, standard panel)

I was really interested in OLEDs from 2019 through 2021, so read all I could and did some deep thinking. What I've come to conclude is 2019 panels will probably prove to be the most durable of the standard panels (everything 2017 through 2021, and LG A/B/and I believe C after 2021).

If 2019 is 100%, 2018 will be 90%, and 2017 will be 60-70% due to early red
subpixel fade. 2020 and 2021 will probably be 80%, and 2022 onwards will probably be 60-80%. These aren't absolute longevity numbers, this is my estimation for panel resilience. TV resilience will probably be about the same due to "optimization" (ie. localized dimming of static elements, image shift etc etc. will roughly equalize the cost saving measures, in..most, circumstances....)

So at 42,000 hours, my A8G has lost 3-5% brightness on all subpixels, with red losing 1-2% more than B/G/W (not a problem, I fixed this in the service menu at 20 or 25k, and soon it will be time for another 1-2% red subpixel boost (no, my TV's not digitally calibrated, but I've got it very close to my calibrated SDR LCDs)).

I've done a few thousand hours of PC use - advice for you:

- make your desktop background a saturated but dark colour, using mostly blue with a bit of green. Blue and green last longest and create the least amount of heat. Also it's unobtrusive.

- auto hide your taskbar. Periodically rearrange any bright system tray icons, especially the red, orange, yellow ones. Also rearrange the default position of your pinned programs about as often

- never maximize your windows, especially ones you have open a lot. It's best to sacrifice a little bit of space than to wreck the edges... You can span the entire width and extend to the bottom (in programs without a status bar spanning their bottom edge), you just need to focus on the file menu/min max exit butons/title area - nothing worse than a dim top right corner from that dang redx

- You have about 1000-1500 hours before bright HUD elements displayed at ~200 nits will start appearing on full grey screens. It's best to adjust the size of the HUD every 300-500 hours, and if you can move stuff around, once you've adjusted the size 4-5 times, rearrange and then go through sizes of that arrangement. If you don't need every drop of performance from your GPU, games in windowed mode and shrunk to 80-95% and put placed randomly every time is good.

every month or two you should do various full colour slides at different saturation. Your display is basically new right now - make 5% grey, red, green, blue, 10%, 25%, and 50%. Display them at 100 nits and know what they look like. If you ever start seeing an element burning in, don't worry, you've caught it in time - you might get a few spots over the course of the lifetime of the display - doesn't matter. As long as they're few and far between and small and not severe, you'll never notice them except as you catch the mistakes which caused them.

If you really want your display to last a long time, get a couple 120mm fans and direct their airflow through the black plastic area behind the panel which contains the electronics. The OLED display will be 7-12 deg C hotter where there is plastic electronics box behind, unless you keep a small amount of air moving through. You can use cardboard and duct tape and a USB port to fan input cable to a splitter. 5V to a 12V 120mm 1800RPM fan will probably spin at around 500RPM: nearly silent and more than fast enough to keep your entire panel at the same temperature +-2 deg C. Why does this matter? Well, often a 10-15 deg C reduction in operating temperature of a solid state device equals a doubling of its lifespan. You don't want the bottom centre of your prized OLED to dim and blue faster than the rest of it... I read of someone who watched anime and cartoons a lot, and after 10-15k hours, the simpsons looked green in the middle and stayed yellow around the top/side edges. Anime and cartoons often have the TV pulling a lot more power than usual though. Normal SDR and HDR movies will average less than 50 watts to the panel for the duration, while, depending on how saturated the colours are, even at low to medium brightness, 200 watts can easily be the average, with peaks over 400 watts. Personally, I was going to run fans through mine, but it got to 10k hours, then I was like "it's too late", and now it's at >40k hours and there's only now just the slightest difference able to be noted.

-If you have white at ~80-150 nits across the whole screen for, say, web browsing, you might notice that, temporarily, where the back of the panel is covered in electronics, after 10 minutes or so, will look 5-8% brighter + have a slightly blueish tint vs the uncovered area. The fan will fix this!

With a fan and the tips above, as long as your control/power boards don't go, you should be able to get >30K hours from your C4. Oh, also avoid firmware updates if they have them. It's a display, if LG has a bad quarter or is sitting on too much inventory

I'm aware of all the fuckery you can try to min max the lifespan. I just turn the screen off everytime I get up and don't worry about game HUDS. I do sometimes play in ultrawide (3840x1600) just for the aspect ratio. The back is never warm to the touch so I don't use fans.

 

[mike7877]

I'm aware of all the fuckery you can try to min max the lifespan. I just turn the screen off everytime I get up and don't worry about game HUDS. I do sometimes play in ultrawide (3840x1600) just for the aspect ratio. The back is never warm to the touch so I don't use fans.

It's not warm to the touch, but it's probably warmer than you think
Most people haven't inventoried all of the materials around them, and how those materials feel at common temperatures.
...I have.
No, I'm not obsessed - it wasn't a mission.. I didn't I didn't do it on purpose- it's just, my IR thermometer gun is always pretty close by whenever I'm working on something, and I use it whenever I'm curious about something or something surprises me rudely. I've had the thing over 6 years now, so I've accumulated a good bit of knowledge. Before actually knowing how various things felt at different temperatures, I had my assumptions (like most people probably do). I was pretty close for many things - especially the more dense materials. It turns out, though, that plastic above skin temperature feels a lot cooler than its actual temperature, and metal above skin temperature feels much hotter. I knew metal would feel hot for its actual temperature, but at literally only 45-47C, you'll get quite uncomfortable within a few seconds. Plastic is more forgiving than I thought, though not to the extent that metal felt hotter. Plastic is like this: if your hand is 20C, plastic will feel close to your hand's temperature from anywhere between 10-12 deg C to 50 C. If your hand is standard hand temperature (bouncing between 30 and 34C), plastic between 20 - 55 is going to feel pretty mild. Going from a 20C piece to a 55C piece, one might assume a 10-15C difference, less than half of the actual 35C.

The longevity of solid state devices is mostly affected by time operating. Temperature adds another dimension to the time. There's a range roughly between 25-45C, and 85-125C. For example, say a capacitor is rated for 4,000 hours at 105C. If that cap is run at 95C, that 4,000 can reasonably be assumed to increase to ~8,000 hours. Drop another 10C to 85, and it's up to 16K hours. Drop 20 to 65C, and cap will live until 64. At 45C, the cap might last over 200k hours.
Temperature ain't the only thing that affects lifespan and span doesn't always double per x decrease. Once time gets to a certain length, other types of component degradation mostly independent of temperatures under 45C start becoming responsible for estimated time to failure, so scaling isn't forever and without boundaries. To finish up, one might expect Mr. 4K cap @ 105C to last 1K hours at 125C (think x2 x2 and /2 /2 like 16k @ 65C from 4k @105), but that's not guaranteed. Even if the rest of the design is stable to 125C, degradation of the active parts might start happening quicker from 110C, leading to failure after 685h. Also, something else could react badly leading to a catastrophic failure after just 40 minutes if that something else fails dangerously (it shouldn't be designed to so close to the rated temp).\

Anyway... If I were you I'd get a slow fan blowing through the back plastic cover juuuuust in case.
I saw a video yesterday that the industry might be doing to OLED what it did to plasma. The author thinks in a year or two, I think it's 5 or 7 years out... If you can get your C4 to last you 7 years, you could plan to buy one of the best ever OLEDs made before they're discontinued forever.... (that is, unless, very soon they start trying to go cheap with OLED, compromising on the aspects which make them great. And capacitors... They might skimp on those near the end too -
Cycle: development, alpha testers, early adopters, enthusiasts, high end consumers, good mainstream devices, cheaper mainstream devices, device quality doesn't matter only costcutting, end of manufacturing.

The C4 has, what I'd consider a "normal" OLED panel - and on the above timeline, appears to have been released between good mainstream device offerings and cheaper mainstream device offerings, slightly closer to good than cheaper. LG/Samsung, at this point, it looks like are at the beginning of being pressured to reduce costs. This might come to the detriment of all panels and nobody will know the true extent of their moral depravity until 3 years later (coincidentally (intentionally?) post-OLED...)

So your C4 could end up being your forever OLED. [ I'd put the fan xD ]
BTW, if you look at a lot of peoples' OLEDs after 10k hours, 15k hours, they're basically ruined and people did many 'tricks'
My suggestions, are tried and proven - I'm at 42k hours with a display indistinguishable from the day it was bought, only ever fixing red shift once at this point (took 5 minutes). I expected the next operation to be between 40 and 45k hours, but the red shift seems to have slowed - maybe 50-55k!
If you display webpages over 60-80% of the screen with white (255,255,255) at 100-150 nits, I _strongly_ urge you to put that 120mm fan (@5V) to keep your panel's temperature consistent across its area. You don't want 60-70% of it to be permanently 8-15deg C hotter than the rest... C4 might be on the way to the cost-cutting arc and be less durable than my Sony C9 equiv. panel

 

[ObjectiveSubjectivist]

Funny.
Till now I thought that only audiophiles are crazy.