Fire TV Cube 2nd gen., TV 4K, a few thoughts on 4K and HDR

[OtinG]

I just recently upgraded to a 4K TV with HDR capability, my first. My previous TV was 12 years old and had nothing "smart" on it, as in no WiFi or ethernet, therefore no apps. Basically it was a dumb TV, but one with a really good HD picture. My new TV is a Sony Bravia XBR49X800H, and it replaced the older Sony Bravia whose model number I can’t remember.

Now to the Fire TV Cube and TV 4K. Both are the latest high end models from their respective companies and both are very good devices over all. I own both and I had both connected to my old "dumb" HD TV. I think the TV 4K produced a bit better video on that old TV, but not by much. However, I favored the Fire TV Cube 2nd gen. for its ease of use and general functionality, and much better remote. Yep the TV 4K remote sucks. Bottomline, you will likely be happy with either device as they are both top notch.

I have now connected the Fire TV Cube and TV 4K to my new Sony Bravia 4K HDR TV. The newer TV has the Android TV smart TV system built in and so I can also use that to view Prime Video, TV programming, and all the other apps from which I stream. The Android TV (version 11, I think) is not bad, it is actually pretty good, but I like both Fire TV Cube and TV better, so I’ll stick to comparing those two.

Although the Fire TV Cube was my favorite on the older HDTV set, it does not seem to produce as good HDR results as does the TV 4K on the new 4K HDR TV. the Fire TV Cube does have HDR10 and other formats and it has Dolby Vision (DoVi), but that latter is available only on some selections. For those who are new to HDR, Dolby Vision is considered the best HDR format available on most TVs in my price range. HDR10 is good, but it is not nearly as good as Dolby Vision, according to most reviews I’ve seen and my own experience. YMMV of course!

Here is why I favor the TV 4K over the Fire TV Cube on my 4K HDR TV. Most streams are not 4K, so they don't have HDR as such. Most streams today are still either 720p (cable TV, some streaming apps, and some OTA) or 1080i (some OTA, some steaming apps). These lower resolutions have to be up-converted to 4K for a 4K TV. So your TV's mileage may vary here as some TVs do a better job than others. Mine does pretty good at this. But regardless of the streaming resolution, the HDTV streams are SDR (standard dynamic range) and not HDR (high dynamic range).

Dynamic range basically deals with how much light an image or video or our eyes can see or display. Digital images and video usually have a lot less range in light that they can capture, so the SDR images will either look okay in bright areas and too dark in the shadows, or they will look okay in the shadows and blow out the whites. HDR allows the extra range of light to be incorporated into the image/video, so that shadows have more detail in the dark areas while the bright areas retain color and detail without blowing out the whites in too bright of an image. Our eyes can see a greater range in light than most digital cameras and video cameras. HDR has to overcome that with technology.

So back to watching a 4K TV with the Fire TV Cube and the TV 4K. Both can produce good HDR. The Cube is restricted, or so it seems, to using whatever HDR format the video has. SDR will not have an HDR format, so none will be used when displaying the HDTV streams. However, the TV 4K will use the Dolby Vision HDR format for virtually everything, if you choose to use it. The result is that colors seem better and if the video has HDR capability then HDR seems better, to my eyes anyway. Again YMMV! On the TV 4K, even live TV streams through apps like Philo and Sling TV, etc. can use Dolby Vision (it is the default unless you change it). All the apps I’ve tried including Netflix, CuriosityStream, Discovery+, Philo, Sling TV, etc. can use Dolby Vision regardless of whether their content is HD SDR or 4K HDR or everything in between.

It is the TV 4K ability to use Dolby Vision for all streaming that makes me choose it over the Fire TV Cube 2nd gen. because this gives me more picture adjustment capability than I have on the Fire TV Cube when viewing non HDR streams. Dolby Vision is a premium format, and I much prefer it to the SDR formats as well as HDR formats. So the capability to use Dolby Vision for every stream (SDR or HDR, HD or 4K) on the TV 4K as opposed to only on some 4K HDR streams on the Fire TV Cube makes all the difference to me. One last time, YMMV!

a couple last thoughts. The Android TV built in to my 4K TV only allows Dolby Vision for some 4K HDR streams just like the Fire TV Cube. I still prefer using the Fire TV Cube for some of Amazon's Prime Video content when that content uses Dolby Vision as the HDR format. The picture quality will be about the same on both devices when both have Dolby Vision enabled for the content. But when the Fire TV Cube content doesn't have Dolby Vision enabled, which is more often than not, I prefer to use the TV 4K so I can use Dolby Vision.

Sorry that this was so long winded, but I thought it might be of some use to others. Until I bought my new 4K TV I had never explored HDR for video. I use HDR in my night sky photography, so I knew what it was and how it can greatly enhance a photo image, but I wasn't up to speed on HDR and video since I had no way of viewing it. Hopefully my learning experience with video HDR and my comments thereon will help you understand it a bit more if, like me, you are new to it.

[OtinG]

4K HDR TV is still very new to me, and I’m trying my best to learn the ropes so to speak. Here are a few things to consider if you want to get a 4K TV in the future. Hopefully my ramblings here in this thread will help you decide whether you are ready to update from HDTV to 4K TV.

Pixel Size and Number

HDTVs have 1920 x 1080 pixels (2 million pixels). 4K TVs have 3840 x 2160 pixels (8 million pixels). So obviously a 50" HDTV will have larger pixels than a 50" 4K TV because the 4K TV has crammed in four times as many pixels into the same screen size. Greater resolution indeed is better assuming you are sitting close enough to actually see the pixels well enough. For an HDTV, the rule of thumb is to sit within a distance of 1.5x to 2.5x the screen diagonal, whereas for a 4K TV the rule of thumb is to sit within a distance of 1.0x to 1.5x the screen diagonal in order to see the pixels well enough to take advantage of the resolution. Sit too far away, and those tiny pixels all seem to blend together and you lose the advantage of the extra pixels. So for a 50" HDTV you should sit between 6.5' and 10.5' from the screen. For a 4K TV you should sit between 4.0' and 6.5' from the screen. I have a 49" 4K TV and I sit about 9' from it, so I’m actually beyond the theoretical optimum viewing distance so I should not be able to see a great improvement over watching an HDTV at that distance. But in reality, I do see added detail, for example skin pores and facial hair show up with greater detail. However, I do agree that my over all experience is that I’m not seeing that much improvement as far as resolution until I move within the optimum viewing distance. So choose the size carefully, but also understand that increased resolution is not the biggest gain you get from going to a 4K TV. The biggest gain is through HDR which provides a huge increase in colors and better lighting for dark scenes without blowing out brighter scenes.

HDR vs SDR

HDTVs use SDR (standard dynamic range) and provide 8-bit color depth which is 16.7 million colors. 4K HDR TVs use HDR (high dynamic range) and provide 10-bit color depth which is 1 billion colors. That is 64 times more colors. However, not all 4K TVs have HDR capability, and even when they do not all 4K content is produced in an HDR format. In my opinion, the added resolution of a 4K TV is wonderful, but the added light and color depth is actually what will take your breath away. HDR make 4K TV worth upgrading to. But do your research. There are multiple HDR formats used for 4K HDR content, the two most common ones are HDR10 and Dolby Vision. Both will knock your socks off assuming your 4K TV can display them. I suggest getting a 4K TV that at least has HDR10 compatibility, but even better has both HDR10 and Dolby Vision compatibility. Unfortunately there isn’t an industry standard yet, and may never be. So make sure your 4K TV is compatible with multiple HDR formats.

BTW, Dolby Vision is poised to be the best format in the future, if not already. It can provide 12-bit color depth which is 68.7 billion colors. That is 68 times more colors than HDR10. Unfortunately, the TV display technology can not yet support nor provide that many colors. Dolby Vision is already top notch, but if the electronics technology ever catches up to it then that will be a game changer.

Notes on TV 4K TV

I mentioned in the first post that the TV 4K TV device defaults all content to 4K HDR Dolby Vision format regardless of whether the original content is HDTV or 4K or has HDR or SDR. I personally like this, but you can change the system defaults to show the original content as it was released. You make the choice. Actually you have a large number of choices you can make about original content and how the TV 4K TV device will display them. It is very versatile.

Notes on Fire TV Cube 4K

I’m disappointed that the Fire TV Cube (or rather Amazon’s Prime Video) doesn’t always stream 4K HDR with the HDR. I ran into several instances where HDR wasn’t included in the stream. That really sucks! I’m not sure if it is a glitch, or whether they are trying to save money. Streaming 4K HDR TV content requires more bandwidth than streaming the same content in SDR.

Notes on Android TV, v. 11

I’m also disappointed that Android TV doesn’t always stream 4K HDR with the HDR. I ran into several instances where HDR wasn’t included in their streams.

YouTube

YouTube does not support Dolby Vision format, so if you stream content with that format it won’t look as good as it should.

Netflix

Netflix apparently has a strange form of HDR. My TV streams it in HDR, but a lot of it is very dark in dark scenes. I tried watching The Crown season 4, and it is so dark that it looks like seeing rooms lit with candlelight. Even outdoor scenes were rather dark. I read this is a Netflix thing and there seems to be quite a lot of disappointment from Netflix subscribers. Hopefully they will start supporting better HDR formats. Some of the Netflix HDR content looks okay, but a lot of it is too dark.

OTA TV and Cable TV

OTA TV via antenna is usually either broadcast in 720p or 1080i. Don't expect to get 4K, probably never. Same with Cable TV as most cable is delivered in 720p with some in 1080i. I wouldn't expect 4K from cable companies any time soon. I have no idea what satellite providers are streaming.

Various Streaming Services via Internet

Some of these provide 4K in various formats, some don't provide any 4K content.

Live TV via Internet

Philo and Sling TV don't stream 4K, as far as I can tell. Not sure if any of the other Live TV services like Hulu do, but probably not.

[OtinG]

Originally Posted by OtinG

Notes on Fire TV Cube 4K

I’m disappointed that the Fire TV Cube (or rather Amazon’s Prime Video) doesn’t always stream 4K HDR with the HDR. I ran into several instances where HDR wasn’t included in the stream. That really sucks! I’m not sure if it is a glitch, or whether they are trying to save money. Streaming 4K HDR TV content requires more bandwidth than streaming the same content in SDR.

The quoted statement was a bit incorrect due to not understanding Amazon's business model for purchasing digital video content. I had purchased several digital movies through Amazon over the past several years. Those were HD content at time of purchase, not 4K. Back then I didn't have a 4K TV so apparently I just purchased the HD versions without even realizing it. Apple, when it debuted their TV 4K device along with 4K content automatically upgraded all of my previously purchased digital video content to 4K, if it was available in 4K, and without a charge. Amazon is greedy and wants to charge more $$$ to upgrade previously purchased HD digital video to 4K, in some cases $6.99 for that upgrade. So look carefully at what you have purchased in the past to see if it is listed as HD or 4K.

HDR content is only available in 4K digital video content, so those older HD movies and TV shows I purchased from Amazon don’t have HDR unless I pay a king's ransom to upgrade them. From now on all my digital video content purchases will be through Apple unless Amazon is the only place to offer a specific title I want to buy.

Note, see next post for a more accurate reason why Prime Video wasn’t streaming in 4K or HDR with my setup. YMMV...

[OtinG]

I have made some discoveries for getting Prime Video 4K to properly stream on my Fire TV Cube 2nd generation device.

In order to get Prime Video 4K to stream I had to use Settings —> Display and Sounds —> Display —> Video Resolution —> 2160p 60Hz.

Using the Auto (up to 4K Ultra HD) option doesn’t seem to work for playing Prime Video 4K with the Fire TV Cube. I’m not sure why, but with my setup it didn’t work. After changing this setting to 2160p 60Hz I was able to stream previously purchased video content in 4K. If you are not in the USA you might need to use 2160p 50Hz instead.

Additionally, I recommend using Settings —> Display and Sounds —> Display —> Color Depth —> Up to 10 bits if your TV supports 10 bits color depth.

Additionally, I recommend using Settings —> Display and Sounds —> Display —> Dynamic Range Settings —> Always HDR if your TV has HDR capability. Using the Adaptive option doesn’t seem to work for playing Prime Video 4K with HDR on the Fire TV Cube. I’m not sure why, but with my setup HDR didn’t work with the Adaptive option.

The Cube seems to require some fiddling around to get it to stream 4K and 4K HDR correctly. I assume Amazon needs to debug the firmware. The TV 4K doesn’t seem to have these kinds of issues.