HDMI Cables Are Obsolete

Yes, I’m shamelessly using a provocative headline to grab your attention. This is an opinion column—you can read my first one here—and it’s my considered opinion that passive HDMI cables are obsolete. Oh, did I leave “passive” out of the headline? Sorry.

If you’re still with me, you’re probably wondering what other kind of HDMI cable there could be. The answer is an active HDMI cable, and I had an opportunity to meet with a company called RedMere this week that has designed an integrated circuit used in the manufacture of the most amazing HDMI cables I’ve seen.

I’ve always preferred beefy cables, thinking that a robust and over-engineered cable would deliver superior performance and last longer. Imagine my surprise when RedMere founder and CEO Peter Smyth pulled out a 10-foot HDMI cable less than one-eighth of an inch in diameter—thinner than most three-foot USB cables—and told me it was 100-percent compliant with the HDMI 1.4 spec, capable of transmitting data at a blistering 10.2Gb/sec.

RedMere doesn’t manufacture cables. They sell the chip that cable manufacturers use to build cables like the one Smyth showed me. RedMere’s customers range from posh brands like Kordzand Monster to mainstream marques like Radio Shack. The chip is mounted onto a module that resides at the end of the cable that plugs into an HDMI display (see above). The chip repetitively samples the incoming signal (effectively performing what’s known as an eye-pattern test) and selectively boosts the frequencies on which an HDMI cable carries data to keep the entire signal within spec.

Active HDMI cables can be both considerably thinner and much longer than passive HDMI cables.

How It Works

Amplifying the signal at the receiving end, Smyth explained, enables cable manufacturers to use less copper for an HDMI cable’s 19 conductor cores and less shielding around those cores, resulting in a thinner and more flexible cable. And since the thinner cable bends much easier than conventional cable, there’s less need to protect it with material such as thick rubber and nylon braiding. I’ve already tossed a couple of thick HDMI cables because I kinked them when pushing my A/V receiver back into my entertainment center (although I must admit that I erred in the design of my entertainment center: I had it custom made when I built my home, and I failed to take into account that every A/V receiver I might use wouldn’t be the size of the one I was using at the time).

RedMere’s chip not only makes thinner cables possible, it can also be used to build longer cables. Smyth told me the longest cable produced to date is 45 meters—that’s almost 150 feet without an inline repeater. Such extremely long cables do require thicker conductor cores and more shielding, but not nearly as much as a conventional HDMI cable would.

Power Consumption

Integrated circuits require power to operate, of course, and the HDMI spec allows just five milliamps of current consumption from its 5V power supply. So RedMere figured out a means—and patented the technology—of stealing unused current from an HDMI signal’s TMDS (Transition Minimized Differential Signaling) lines that carry video, audio, and auxiliary data. “We never take any power from host device,” Smyth said, “that’s the last thing you want to do with a handheld device operating on battery power.”

Smyth thinks active HDMI cables are a boon to handheld devices because their narrow diameter renders them extremely flexible and easy to carry. “I never use a notebook for presentations any more,” Smyth said, pulling a BlackBerry Playbook out of his bag. “I carry a tablet like this one and connect it to a TV. I can easily carry an 15-foot active HDMI cable with me, where I’d never do that with a bulky passive cable.”

Pricing

Active cables, as you’ve probably guess, cost more than passive cables. A 10-foot PNY-brandedactive HDMI cable (High-speed with Ethernet, A-to-A connectors) using RedMere’s technology costs about $38 on Amazon. A passive HDMI cable of the same length and specs with swivel A-to-A connectors from Rosewill (I use this particular SKU because the swivel connectors eliminate kinking problems) sells on Amazon for about $15. But remember that active HDMI cables are manufactured using fewer raw materials—particularly copper—than passive HDMI cables. Smyth maintains that by the third quarter of this year, we’ll see active HDMI cables selling for less than passive HDMI cables.

What do you think of active HDMI cables? Do their flexibility, extended length, and durability make them worth today’s price premium, or will you wait until they reach parity with passive cables before taking the plunge? Let me know your thoughts in the comments section. And if you’d like to follow me on Twitter, my handle is @BrowniesHQ.