Beware the Latest HDMI Claims Surrounding Rev 2.1

Do all sheep lie? For those of you familiar with this phrase, kudos — this means you attended one of our presentations and remembered this funny comparison between what is real and what isn’t. So let’s discuss some additional examples of claims that enter into the “Sheep Lie” Hall of Fame. As we move deeper into 4K and 4K/60, plus HDMI expansion of Revision 2.1@48Gbps, the need to reliably carry high data rates through long transmission lines is bringing in new creative ideas.

One of the great things about free market competition is incentivizing designers to reach out to the edge and start creating products that can solve problems while at the same time do it for less money. But we need to be careful and scrutinize potentially dubious Hall of Fame claims from manufacturers.

Many unproven claims in our industry result from a lack of updated information and data. A perfect example happened with HDMI Rev 2.0.

This revision came out in September 2013, announcing 4K/60 with a bandwidth increase from 10.2Gbps to a whopping 18Gbps. Except not many recognized that its initial deployment was to start by eliminating other technological gains made years earlier; the color department in particular. Color sampling was reduced to 4:2:0 and color depth was limited to just 8 bits, a huge contrast from what was marketed so heavily in earlier revisions.

Any new announcement like this always brings on a feeding frenzy from the manufacturing community; in this case with a race to be first to market with 4K/60. But due to limited information on the subject, much of what was produced was not 4K/60 and was not the Deep Color to which we had grown accustomed.

It was also not 18Gbps. Most suppliers did not realize it until long after, when HDR (high dynamic range) was announced the following year. So integrators were selling to their end users a new 4K/60 product, not realizing that they were operating at legacy Rev1.4 levels. Just a little bit more knowledge and this could have been avoided.

Now, the phones are kicking up again because those integrators who did not fully understand ended up installing transmission lines incapable of handling the entire 18Gbps service envelope; they were not told they were selling and installing lower quality 4K/60 products.

Yes, sheep do lie and it is “baaaaaaaad” for you.

HDMI, Fiber and Copper Products

As an independent testing agency, we get to see all kinds of products that enter into our field, some really good and others that should be used as paper weights. And as you would guess, many products claimed they were transmitting 4K/60 but were really fiddling around 10.2Gbps and not 18Gbps. Others, however, were very successful when making that long reach out to 18Gbps.

Our friends in the active copper business continue to build for 18Gbps, and now there are some new players that again “claim” they can handle the entire bandwidth to support cable distances that are longer than what passive cables can achieve.

Some are doing a darn good job, while others can’t make it over the critical HDMI 5-volt power limit. This goes right into the Sheep Lie Hall of Fame. They send these products out knowing full well they breach the voltage limit.

DPL Labs: HDMI Rev 2.1 Has Phones Ringing Off the Hook

You also have the new fiber products entering the field. Some of these fiber products are fantastic and can go many meters in length — just be sure what you are installing.

Besides fiber, we are beginning to see 48Gbps transmission line products pop up in copper, too. That’s right, copper. We will be watching this very closely and will report in as we get more data, especially on sheep that are claiming to reach 48Gbps.  

We have shifted to some newer test equipment and software to analyze these high data rates better, and are finding that some of these products are looking very good under current test criteria. That isn’t to say they can’t be even better supporting higher data rates, because we are confident there will be even more corrective EQ implemented in sink (display) devices aiding 48Gbps products even more; only time will tell.

It’s imperative to ask the right questions when using these products. Don’t be shy, just ask. Not all sheep lie.