Do expensive HDMI cables make a difference? - article discussion

Firstly , no cable longer than 8 meters has ever passed the high speed test suite ( category 2 ), however , the high speed test suite has always tested to 4096 x 2140 ar 60 fps ....so assuming it fails at some point between 1080p and that early assumption of 4K, a longer cable may well be fine for 1080p....cables as long as 15 meters have worked for 1080p...they just wont ever have passed and gotten a genuine certification so there are no guarantees.

Second, general rule of thumb is never run signal cables beside mains cables.
That is a rule everywhere.
The magnetic field from a mains cable is of a strength that can swamp any signal carrying cable.

Having said that, HDMI cables built to spec have a complete metallic outer shield that should be able to handle it ( faraday cage etc.)
Its still good advice not to do it though.

There is little magnetic field from even a twin unscreened mains cable. The live and neutral return currents being opposite work similarly to a twisted pair network cable and largely cancel any external 50Hz electromagnetic radiation. . In any case the frequencies involved in HDMI interconnects are way higher than the main at 50Hz,

Seen this many times, never experienced any issues at all, unlike poorly screened coax interconnects carrying UHF in close proximity to HDMI cabling.

All the regs regarding seperation are purely down to electrical seperation from medium voltage cabling and low voltage cabling. A plastic screen is fine which clearly has no effect at all on induced voltages. It's purely based on on cable damage like for say drilling through both cables buried in a wall.

I speak as a ex National grid Engineerof 40 yrs experience. Even a unbalanced 400KV overhead line of many miles carrying up 4000MW, only requires the transposition of the conductors to cancel the unbalanced induced currents over a very long distance, while 3 phase cables require none.

So sorry your rule of thumb has no foundation at all, it has no foundation in any electrical sense.

A fully screened HDMI cable is not a Faraday cage at all. Electromagnetic radiation will pass through it unchanged. Only a screen of a ferric based composition as used in a transformer core will have any effect all. Basically a transformer.

A Faraday cage has no relevance at all. It merely reflects that within a metallic box that all internal points are at the same potential. If you are in a Faraday cage (Aircraft - Car, that is struck by lightning), then whatever you are touching is at the same voltage so no current passes through your body - so you feel nothing. Birds sit on high voltage overhead lines, if they happen to peck on a earthed point they die instantly. Voltage isn't the issue it's the current that passes through your body that can kill you.

It has absolutely nothing to do with external induced inteference.

Edit

Incidentally my car is a Faraday cage as everyone's ones is.

Like everyone else my 4G phone works just fine.

Please explain how your theory explains this.
 
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Wonder what the average price will be when ultra high speed cables are the norm.
 
Whatever people will pay.
 
There is some issue with HDMI.org and certifying active cables via their ATC (Authorized Testing Center) program. Currently, no active cables can receive certification, as noted by the QR label, whether they be copper-based, fiber, or hybrid fiber-based. Once cables, as well as their connectors pass the CTS requirements for HDMI 2.1, the cables will be designated as Ultra High Speed HDMI cables to distinguish them from Premium High Speed HDMI cables. Any cable at this currently that is being marketed as Ultra High Speed HDMI is questionable imo. There has even been some discussion as to the "Belkin" cables being sold last year, before the final ratification of the HDMI 2.1 specs, were actually Belkin cables. Cable mfrs in general have been getting away with all kinds of claims for a long time and unless you frequent these forums (which admittedly is for us OCD types) the general population will buy into their hype and purchase the cables at what ever price their marketing and slick ads determine.

Reliability for full, HDMI 2.1 compliance (48Gbps) is the current issue for lengths longer than the original HDMI 2.1 specification, which was 1m - 3m. Power requirements seem to be the issue. Prototype cables were shown at this year's CES but they were only prototypes and not read for prime time.

What I would like to see is the cable mfrs list which HDMI 2.1 hardware specifications their cables meet and not just label them as Ultra High Speed HDMI.
 
Whatever people will pay.

I hope that when they start rolling off the production lines they come in under a tenner. The Apple/Belkin marketing ploy, I wonder how many they sold. Of course there will be the usual suspects trying to flog them to the unsuspecting.
"Better future proof your TV now sir and madam" (even though they will not have 2.1 hardware).
 
Always was going to be an issue with faster speeds on a passive cable. Wonder why they did not go down an optical option connection, that is a physical port on devices?
 
'Wonder why they did not go down an optical option connection' - at a guess I would presume a huge loss in Licence fees!

Joe
 
I wonder how much HDMI to fibre adaptors could be made for.
 
Hi Joe. I agree with you, and something I've been saying for quite sometime. 3m max is going to be a killer for a lot of systems. I do know that there are issues right now with power consumption and the longer cables, as well as eARC at the 30m length so this should be interesting for the marketeers. What I would like to see is Ultra High Speed HDMI cables labeled with the HDMI 2.1 options that the cable has been tested for and not just indicate "HDMI 2.1". HDMI.org currently does not allow active cables to be certified (certified with the QR label) even though the cables are tested by an ATC (Ruipro does this), so stating which HDMI 2.1 options the cable has been tested for is critical for the consumer. Hopefully the smoke and mirrors won't be so thick once HDMI 2.1 is out in the wild that the consumer doesn't get too confused.
 
I wonder how much HDMI to fibre adaptors could be made for.

So far only the connectors have been submitted for CTS testing so adapters are still a ways off. Pushing 48Gbps down a copper cable is tough enough but then bridging to a fiber adapter and still maintaining signal integrity is very challenging. For the early adopters, a single connection, source to sink is probably going to be the only option for quite some time. Hence, all new cabling. Start laying in that conduit now if you haven't done so yet ;-)
 
'I wonder how much HDMI to fibre adaptors could be made for' - look at Celerity and similar 'two piece' designs, they tend to be more costly and in our experience less reliable (both physically and in terms of signal support) than the Hybrid Fibre' option.

Joe
 
Any recommendation, which is not very expensive, to connect the nvidia shield TV to my Samsung Q90R TV, for HDR +? and have no problems? I need about 1.5m or 1m approximate
 
Assuming you have one already try using whichever cable you have to hand - for the most part any 2m cable will work for you.

If you happen to not have a spare cable lying around and want a bit of extra ’assurance’ look for a cable which carries the official Premium High Speed or High Speed Certification Logo.

HDMI :: Manufacturer :: HDMI 1.4 :: Finding the Right Cable

Joe
 
Interestingly I have just had my HDMI cable 'experience'. I linked my Sony 4k player directly to my new Optoma UHD51 using a 5m juicebitz cable from Amazon that was recommended on these forums, and 4K blu-rays played fine. However, the home screen and any internet app e.g. Netflix, Prime, flickered like crazy. I tried every variable in the player and projector menus and nothing fixed it. Finally I took it back to Richer Sounds and they could not reproduce the fault, so the manager kindly sent me home with a 5m Audioquest Pearl cable loaner. Now everything works fine.
It makes no sense - the 4K disks are being transmitted at 4K (obvs) and the old cable was handling this OK whereas the internet apps are only in HD. Anyway, I don't care; I'm just pleased to have it working.
 
I've had a stroke of luck with my HDMI lead. Many years ago I had to replace a 15M DVI cable that couldn't handle 1080P signals and due to the cost of long HDMI leads I think I replaced it with a 10-12M (cant remember which) Supra HF100 lead which worked well, as it should since it cost £130. Following the update to 4K I believed I was about to have to fork out again for a new lead but I've just plugged it in and success! 4K hdr hurrah! not tried any high frame rate material but with films its working fine. Watched several films without any drops or glitches at all.
Cant believe it, I normally strike out on these kind of things.
 
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I'm looking at getting a cable for my computer and Ultra Bluray player it has to support 4k HDR+ at 100fps for the computer and another that can support 24fps with Dolby Vision. I don't get why over 18GBs are needed for 4k at 100fps there's only 50GB on a 4k bluray.

Narrowed it down to the 2m Belkin 18Gbs and the 48Gbs
 
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The 50GB on the disc is compressed heavily and it is decoded before being sent to the TV.
 
At 2m you may struggle to find a cable which won’t work :)

Have you tried your existing cables?

Joe
 
No, digital video has been compressed for decades.
That includes the Star Wars box set!
 
All DVDs and Blu-ray discs use video compression. DVD video commonly used MPEG4, Blu-ray used H264 and UHD discs use H265. Guess what 8K will in all probability use …

yep, H266 :)


Without the compression, you'd have difficulty fitting the data on the media. You'd also need a lot more bandwidth to stream video via the streaming services and TV services.


Even with compression, you're not going to fit 8K content onto physical discs and nor is there any move to create optical discs that will accomodate it.


Understanding MPEG-2, MPEG-4, H.264, AVCHD and H.265
 
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No, digital video has been compressed for decades.
That includes the Star Wars box set!
Right got ya. My 24 million pixel photos in Tiff format are 896Mb thats in bits so 18Gbs does seem high. No idea on how much the HDR data and sound takes up though.
 

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