ARTICLE: Which HDMI cable should I use for 4K HDR?

@gibbsy Noooo LOL. 4:4:4 is like the same as RGB and RGB has been around since before the 1980's !!

That's what I'm wondering though, maybe 4:4:4 when run in that mode at the "same time" as HDR + 4K + 60Hz is beyond the capabilities of HDMI 2.0 ports !!

As said above, you can't send 4K60 4:4:4 with HDR (22.28Gbps) to an HDMI 2.0 port as HDMI 2.0 tops out at 18Gbps.

Does your TV have HDMI 2.1 capability?
 
@gibbsy Noooo LOL. 4:4:4 is like the same as RGB and RGB has been around since before the 1980's !!

That's what I'm wondering though, maybe 4:4:4 when run in that mode at the "same time" as HDR + 4K + 60Hz is beyond the capabilities of HDMI 2.0 ports !!
It's the bandwidth associated with it not the format itself when, as mentioned, part of HDR and 4K presentation.
 
Because Chroma is really important. I mean If you operate a 4K TV at 4:2:0 Chroma then all you've really achieved is to turn an expensive 4K screen into a 1080P resolution!

Blu ray disc is mastered at 4:2:0 it doesn't go any higher - 4K HDR 4:4:4 gaming doesn't exist yet as how you want it and I doubt there's any titles currently where you can get high fps, 4k and HDR especially via HDMI. Display port may be a different matter however.
 
As said above, you can't send 4K60 4:4:4 with HDR (22.28Gbps) to an HDMI 2.0 port as HDMI 2.0 tops out at 18Gbps.

Does your TV have HDMI 2.1 capability?

Now that makes sense!!! So I need to wait for v2.1 HDMI ports then. No my TV doesn't have a v2.1 port :(

PS: I think the HDMI 2.0 port must top out at more than 18Gbps in real life because otherwise the 27Gbps and 48Gbps HDMI cables wouldn't perform any better than the 18Gbps Amazon Basics ones :/
 
PS: I think the HDMI 2.0 port must top out at more than 18Gbps in real life because otherwise the 27Gbps and 48Gbps HDMI cables wouldn't perform any better than the 18Gbps Amazon Basics ones :/

Nope. That will totally depend on the quality of the cable, nothing to do with what the HDMI port is capable of.

BTW, you really can't trust what many HDMI cable manufacturers claim.
 
All of the Certified HDMI 2.0 cable’ - are incorrectly labelled/advertised.

HDMI Cables are not version compliant - you cannot ‘certify’ an HDMI V.anything cable.

Cables have a separate system of categories - Standard, High Speed, Premium High Speed...

Joe
 
What Joe said. If your run is under about 20' (6m) then a Premium High Speed HDMI cable (with the QR label) is what is recommended for 4k HDR. Over 20' or so a hybrid fiber cable (Ruipro4k) is recommended. No one has a cable yet that has been certified for the HDMI 2.1 hardware specs, regardless of the slick marketing.
 
For a 3m cable run can anyone explain why the 27Gbps and the 48Gbps HDMI cables both enable the TV to run on better picture settings with a noticeably more colourful and vibrant picture than the Premium Certified cables that come with the QR labels?

I'm operating with a PC and while all Premium Certified High Speed HDMI cable's with the special QR label did allow me to run 4K 60FPS HDR10 content with 4:2:0 Chroma I was not happy with this because I know the TV will go to 4:4:4 Chroma.

So I spent the money on a 27Gbps cable and this gave me a new option in the settings which allowed the TV to operate at 4K 60FPS HDR10 content with 4:2:2 Chroma.

While this was a definite improvement in picture I still wasn't happy with it because I wanted 4:4:4 Chroma like the TV can definitely do, so then I purchased a 48Gbps Belkin branded cable thinking that would definitely get the job done but to my disappointment this gave the same 4K 60FPS HDR10 4:2:2 Chroma picture that the cheaper 27Gbps cable had done. At this point I was very disappointed, angry and confused.

The only way I seem to be able to get a 4:4:4 Chroma picture is by turning down the resolution to 1080p HD, and this then allows me to operate at my TV's maximum frame rate with the following settings: 1080p HD 120FPS HDR10 4:4:4 Chroma which is an incredibly colourful and vibrant picture but detail is definitely being lost because it's only 1080p HD and not a 4K resolution anymore :/

So yes, why do the 27Gbps and 48Gbps HDMI cables give a better picture than the Premium certified High Speed 18Gbps HDMI cables that come with the authentic QR bar code labels??

It seems like sticking to the original High Speed, Premium High Speed descriptions is somewhat confusing because Premium High Speed just means the HDMI cable can achieve a minimum speed of 18Gbps doesn't it, which implies that 21Gbps, 23Gbps, 27Gbps and 48Gbps HDMI cables which are all faster higher performance cables are still described as Premium High Speed HDMI Cables. It's all very confusing for somebody simply trying to pick the cable to give them the best picture :(
 
So I spent the money on a 27Gbps cable and this gave me a new option in the settings which allowed the TV to operate at 4K 60FPS HDR10 content with 4:2:2 Chroma.

Probably because they're better cables. 4k HDR 4:2:2 is still possible with HDMI 2.0

Ruipro or Monoprice Slim Run AV cables are the only ones that give proper consistent result. Nigel Archer from Arrow-AV did a big cable shootout a while ago:

https://www.avsforum.com/forum/168-...ly-support-18gbps-hdmi-2-0b.html#post52755273

And there's an update in there for HDMI 2.1 as well - I was involved in this test and still have the Slim Run AV 10m cable on my system.
 
Probably because they're better cables. 4k HDR 4:2:2 is still possible with HDMI 2.0

Ruipro or Monoprice Slim Run AV cables are the only ones that give proper consistent result. Nigel Archer from Arrow-AV did a big cable shootout a while ago:

Thanks Mr/Mrs Danger :p

I'm in UK so don't have those options available to me here but that's a really useful report and exactly what should be available to all as a quick Google!

What do you mean when you say consistent though? Are you saying that some HDMI 2.0 cables work intermittently as in they will work one day on setting "A" and then tomorrow if you tried watching exactly the same thing on setting "A" again they would not work?? #Minefield!!
 
@AWCrypt it should be available but no one at the time other than Arrow-Av actually sat down and did a full mad scientist test on them and he had no bias either - He's a custom installer and along with other CI's I know they were getting fed up with stuff failing all the time due to either bad craftsmanship or various differentiation in handshaking.

Consistent as in it does what it's meant to do on a bunch of different equipment in the wild as well as the industry cable testing gizmos. Yes, exactly.. some days things will just not work, it used to be so much worse than this.

Any decent AA will sell you a cable that wont be shit - @themovierooms Dan should carry stock of Ruipro and has lots of knowledge on this stuff.

Yep, just checked.. still a Mr!! :rotfl:
 
There are only two recognized bandwidths for HDMI cables, 18Gbps and 48Gbps. Premium means that all of the HDMI 2.0 hardware specifications have been tested and certified by standardized testing protocols. Once testing and validation is completed for HDMI 2.1, the cables will probably be labeled as Ultra (once the term is trademarked by HDMI.org like they did for the Premium label). Ultra will mean that the cable has been tested and certified for all of the HDMI 2.1 hardware specifications to separate them from Premium cables. Any bandwidth claims other that 18Gbps or even 48Gbps are suspect because there is no way to determine how those claims were verified. It's easy to put some sort of pattern generator at the end of a cable set in a straight line and make claims but its an entirely different matter to actually test the cable in a real world setting with current consumer devices. The cable is just a digital data pipe. It can not make the reds any redder or the greens any greener. There is more to a successful connection than the cable. If you don't get any sparkles, dropouts, etc then you're getting the best signal you can. For runs under 6m or 7m, I'd recommend a Premium High Speed HDMI cable. For runs over 7m, I'd recommend a hybrid fiber cable like the Ruipro4k. If the cable run is in-wall then using a conduit is an absolute must.
 
The cable is just a digital data pipe. It can not make the reds any redder or the greens any greener. There is more to a successful connection than the cable. If you don't get any sparkles, dropouts, etc then you're getting the best signal you can.

I kind of agree with you to some extent but if what you were saying was completely true then my hardware wouldn't give me additional picture options simply by swapping a 18Gbps cable out for a 27Gbps or 48Gbps one so I think there must be more going on here than simply either getting a picture or no picture at all.

I think the devices are somehow handshaking with each other to ascertain what the best picture setting available is, and then those better picture options are being shown as selectable options when those better cables are connected. Because this is exactly what I am seeing on my setup...

With the 18Gbps cables connected and with 4K 60Hz HDR10 options selected the system only shows the option to have 4:2:0 Chroma, but as soon as I swap that cable out for either a 27Gbps or a 48Gbps cable then with the same 4K 60Hz HDR10 options selected the system shows me the additional option of being able to choose 4:2:2 Chroma... then as soon as I swap the cable back for the 18Gbps one the Chroma option goes back to being only 4:2:0. So there must be some kind of data flow between devices down the HDMI cable that is somehow letting either one or maybe both devices know what the maximum data flow down that cable is.

I think this handshake is somehow lengthened on some devices too because a friend of mine bought a 27Gbps cable to get the 4:2:2 Chroma and told me that the screen went completely sparkly for about a minute and then after that the picture has been a perfect 4K 60Hz HDR10 4:2:2 Chroma picture every since. It's very strange, I think it should just work or not work instantly but there is obviously some other kind of voodoo magic going on in the background on initial installation of a new cable :D

I wonder why a solid cable with no moving parts can work one day and not work the next. I'm not saying it's not true but I'm very intrigued to know what is going on inside the cable to make it behave in that way. I mean there must be soldered joints to terminate the actual cables inside onto the pins so maybe some of the cables are manufactured using poor soldering conditions or something. I mean the data flow isn't so high that the solder is melting in operation is it???
 
Nothing is going on inside the cable. It's just passing data back and forth. How that data is interpreted is a function of the HDMI chipsets at the source and sink end. If you have a single connection, source to sink, with no adapters, switches, extenders, etc in-between then whatever the source sends you will receive at the sink end as long as it is a well made cable and you don't have any sharp bends or stress on the HDMI inputs. A "27Gbps cable" is pure marketing.
 
Hi Otto, sorry but that doesn't make sense because I have seen the difference in picture options the different speed cables give first hand.

I agree with you that nothing should be moving inside the cables other than electrons and that the cables are just a conduit to pass information back and forth but all the different speed cables give different results when attached in exactly the same way to the source and TV output ends. I have definitely seen this, but as described, I've yet to find any solution which gives me the 4K 60Hz HDR10 4:4:4 picture I want. Not even the 48Gbps cables give me that on my devices, but I think that's because the HDMI 2.0 ports are maxing out well below the cables performance potential.

I imagine when you attach a 27Gbps or a 48Gbps HDMI cable to HDMI 2.1 setup then you will see 27Gbps and 48Gbps speeds being attained.

I mean 48Gbps is the newest v2.1 standard and 18Gbps is the old v2.0 standard so it must be possible to design a cable to perform to 21Gbps, 23Gbps, 27Gbps, 30Gbps, 35Gbps 40Gbps and everything in between.

There is definitely a lot of false marketing going on in the area of HDMI cables though because I have purchased so many cheap 18Gbps cables that do not even play 4K 60Hz and look more like the older v1.4 HDMI cables. People are probably getting away with this false advertising because the older v1.4 cables do play 4K 30Hz and well most 4K content is only played at 4K 24Hz, so most people don't realise they've been ripped off until they start seeking out better quality content. This better quality 4K 60Hz HDR10 content is readily available now and it's with this content that having a cable that performs above 18Gbps works better, at least for me in my setup anyway, but data is data and the amount of data to give a 4K 60Hz HDR10 4:2:2 picture will be the same no matter which device a person is using.

I think someone needs to do a real world side by side test of all these false cables to advertise to people which cables simply do not perform as advertised so that people can start making informed choices, because HDMI cables are a really confusing area.

I saw a HDMI cable the other day for 159 GBP which is insane, it wasn't even a 48Gbps cable LOL but a 27Gbps cable with a bit of carbon fibre on it. The brand name was Monster LOL and well that's just very expensive for a cable.

I think the only thing going on inside the cable is limited to the flow of electrons and the electromagnetic effects associated with that flow of electrons. There's probably more complicated stuff like eddy currents etc going on as well but that's probably a topic for a different type of forum than this. But if anyone knows this science stuff I would be very interested to learn more :)

As far as sharp bends and stress on inputs, as long as a good electrical contact has been established on each of the HDMI pins at either end of the cable then the electrons should flow just fine. I imagine the data flow has got to be a function of the resistance of the cable and the resistance to outside electromagnetic interference, so I guess the higher speed cables must be made of something similar to high speed internet, so coaxial cable or potentially also glass fibre :/

I was interested to see that the very expensive glass fibre cables are only rated to 18Gbps though... I didn't buy one LOL
 
The problem with using your findings as anything 'definitive' being the Manufacturer/Brand 'claims' about cables supporting a particular Gbps figure cannot be verified and your findings may differ with one other change in the signal path.

The HDMI certification process is not just on the cable bandwidth - it also covers the whole production chain.

Have you enabled 'WCG' on all Inputs of your LG TV? That can catch you out when you are using multiple Inputs on some LG models as they only come enabled for HDR on the ARC Input - even though other inputs have that capability it is often disabled as the default setting.

A little 'out of date' now but worth a read if you do want more info on what goes on under the skin with HDMI - HDMI Uncensored | Inside HDMI

Joe

PS If you do require a long HDMI cable then RuiPro4K are not that difficult to find in the UK :)
 
The cable doesn't determine the speed, it's the devices connected in-between. IOW, the HDMI chipsets at source and sink. The cable is designed so that it can reliably achieve that bandwidth if presented by the source. A cable can be tested at a higher bandwidth but that doesn't mean it will transmit signals at that bandwidth. For example, the new Ruipro8k hybrid fiber cables are being tested and validated now for the HDMI 2.1 hardware specifications which is 48Gbps. However, during the testing phase the cables were able to reach 52Gbps before issues arise. All that means is that the cable will be able to reliably handle a 48Gbps signal when presented. If you think that a "27Gbps cable" is offering better pq on a signal path that maxes out at 18Gbps then that's fine. It's all in your head.
 
Thanks Joe, useful information. Luckily the HDMI cable was tested in the ARC input port :)

Otto, I think we're going to just have to agree to disagree on this one. All I can say is the 18Gbps HDMI cables did not give me the higher performance 4K picture options and the 27Gbps and 48Gbps HDMI cables did, and then when I switched back to the 18Gbps cable again those better picture options once again disappeared. There's definitely a real world performance increase happening here and it's not in my head... but then I guess the world used to be flat until somebody showed it wasn't :)

From what you're saying it sounds like some of the 18Gbps HDMI cables might work slightly beyond 18Gbps, perhaps even reaching the magical 22Gbps number that seems to be required for 4K 60Hz HDR10 4:2:2 Chroma, but the point I'm trying to make is why waste time and energy buying many 18Gbps HDMI cables to find the one which works to this higher standard instead of just buying a 27Gbps or 48Gbps cable and knowing it'll work first time and will also provide even better performance in the future when you start buying HDMI 2.1 compatible devices.

I'm not saying you don't happen to have a 18GBps HDMI that isn't working, I'm just pointing out that I bought several 18Gbps HDMI cables and none of them worked for me, but the very first 27Gbps and 48Gbps cable I used worked first time and it is easy to understand why that would be the case.

And I'm also pointing out that when you can buy these higher performance HDMI cables for the same price as the lower performance 18Gbps HDMI cables then why would you ever buy an 18Gbps cable again.
 
How do you know that the cable is actually tested and certified for the 27Gbps? Did you get a Certificate of Compliance with the cable or are you just taking the cable mfr's word for it?

4k (3840)@60Hz with 4:2:2 chroma can be achieved at 17.82Gbps with HDMI 2.0 hardware.
 
Ummm there is no certification program for any cables above 18Gbps yet.

4K 60Hz HDR12 4:2:2 Chroma?

Seem to remember there also being an option for 5K 60Hz too but my screen is not a 5K screen so I didn't try that option :/

To be fair my graphics card is pretty decent and the HDMI output port is rated to 8K 60Hz so I think the computer is somehow able to determine the speed capability of the HDMI cable being attached and make those options available to select when the higher speed cables are being attached... I can;t think of any other explanation :/
 
That's my point. You have no idea how the cable mfr's claims for 27Gbps (which is an odd number to begin with) or even 48Gbps were verified, especially in a real world setup not some R&D lab. There aren't any consumer devices and/or source material to check. The cable just passes 1's and 0's back and forth, and if there aren't any error correction, timing, etc errors then you get the picture as was originally encoded and sent.

And speaking of certification, only passive cables can be verified by an ATC. HDMI.org doesn't allow for certification of active cables so hybrid fiber cables, which is your best bet for runs longer than about 20' can't be certified either because they are active.
 
Hmmm my point isn't how 27Gbps or 48Gbps cables have been verified to work at these speeds. It is clear by now that each 18Gbps certified cable will hopefully have been tested to function at 18Gbps under at least one quick fixed condition test, and the first few ever made which would have been manufactured very carefully by the most skilled worker available will have been more thoroughly tested to prove the design functions at 18Gbps under varying expected real life conditions too.

My point is that the 27Gbps and 48Gbps HDMI cables I tested were all faster and better performing cables than every 18Gbps cable I have ever tested. I've mentioned how the HDMI 2.0 ports maximum allowable speed is 22Gbps, so these 27Gbps and 48Gbps cables only have to function to 22Gbps in order to give the best picture possible through those HDMI 2.0 ports. But to give the same better picture an 18Gbps HDMI cable would have to try and function 20% better than it had been designed and manufactured to do. So it seems much more likely that the 27Gbps or 48Gbps cables are going to perform to 22Gbps than the 18Gbps. It's a fairly simple point I'm trying to make.

But I do take your point that when no ISO standard test is yet in existence to test that 27Gbps and 48Gbps cables do actually perform to 27Gbps and 48Gbps respectively then the manufacturers must have either designed the extra performance theoretically and then tested it, or simply used trial and error approaches to design a cable which when tested gave the speeds they were looking for likely using lab test equipment rather than a bespoke test machine designed to a predetermined ISO standard.

But just because an ISO standard test does not exist for these cable speeds yet does not mean that the manufacturers were not able to successfully test the cable design to work at those speeds.

I imagine you're going to say well they probably tested the cables in a straight line and in real life cables are bent around corners etc which loses a bit of speed, but the point I am trying to make is that the 27Gbps can afford to lose almost 20% of it's speed and still perform to the best picture settings possible through HDMI 2.0 ports, and the 48Gbps cables can afford to lose over 50% of their speed and still perform to these best picture settings possible through HDMI 2.0 ports, but as mentioned the 18Gbps cable would have to magically perform 20% better than they were designed to perform to.

It's pretty clear to me why in my tests both the 27Gbps and 48Gbps HDMI cables all outperformed every 18Gbps HDMI cable. It's undoubtedly a complex subject area but the logic is fairly simple when you can affrod to lose such a large percentage of the performance and still attain the best picture quality possible.
 
<sigh> It's all 1's and 0's. You can't make reds any redder or greens any greener. You either get the signal or you don't. Who is the mfr of the supposed 27Gbps cable and the supposed 48Gbps cable?
 
Hi Otto, you're correct it's all 1's and 0's. The higher quality pictures require more data to produce which means more 1's and 0's and that's why the faster HDMI cables allow for a better picture.

But that's what I'm saying. The maximum data speed of the HDMI 2.0 ports is 22Gbps so the best picture you can get on devices with HDMI 2.0 ports will be a 22Gbps picture. So why would you buy an 18Gbps cable to get a 22Gbps picture, it makes no sense as the 18Gbps cable is not designed to be fast enough to carry all these extra 1's and 0's.

27Gbps and 48Gbps HDMI cables are able to send more than 22Gbps of data down them so this allows for all the 1's and 0's required to make that 22Gbps best possible picture to be sent successfully down the cable.

And what I am saying is yes the reds do instantly appear redder and the greens do instantly appear greener when the picture is increased from 4K 60Hz HDR10 4:2:0 Chroma to 4K 60Hz HDR12 4:2:2 Chroma and the only way I achieved this was by using 27Gbps and 48Gbps HDMI cables because the 18Gbps ones just did not allow enough 1's and 0's to be sent down it to achieve the better 22Gbps picture.

I can't remember all the manufacturers names. Monster comes to mind because that's the expensive one which left the biggest impact on my wallet, but all of the cheaper ones worked for me too. I don't think it's about manufacturer, it's simply about the cable being either a 27Gbps or a 48Gbps cable, and of course it's always about everything else in your setup having a minimum of HDMI 2.0 support, so the source needs to be a minimum of HDMI 2.0 and the TV needs to be a minimum of HDMI 2.0, and as Joe mentioned earlier it could also be important to connect that higher speed cable to the HDMI ARC port as apparently the ARC port could be the only port capable of HDR. I've now tested that and it's not the case on my TV as all HDMI ports give the same better picture when used with the better cables.
 
More 1's and 0's? Seriously? You are assuming that ALL HDMI 2.0 inputs can handle a 22Mbps data stream without issues. There's a reason that HDMI.org capped HDMI 2.0 specs at 18Gbps. And you're also assuming that a 27Gbps cable has actually been tested and confirmed to pass data at that speed without issues and still meet HDMI 2.0 specifications.

I don't use ARC or eARC and I have no issues at all whatsoever passing 4k HDR (Dolby Vision or HDR10) using any of my HDMI inputs with Premium High Speed HDMI cables or hybrid fiber cables. PQ is the same because my OLED panel is getting all of the data that the source is sending, including uncompressed audio when presented regardless of input used or cable type.

HDMI is backwards compatible but you will only get picture and sound at the in-common protocol sets. IOW, an HDMI 2.0 source sending to an HDMI 1.4 sink will only be able to successfully and reliably utilize the HDMI 1.4 option sets. The cable has nothing to do with it as long as it is a well made cable. Monster and AudioQuest make good cables but their cost is not justifiable imo because you get the same performance out of a similar, well made cable at the same length for a lot less money.
 

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