Why all HDMI cables are the same, part 2

Debunking a few more HDMI cable myths.

HDMI.org

A few months ago, I wrote the provocatively titled " Why all HDMI cables are the same ."

There was a ruckus. Which I expected.

But the post also generated some great questions. Which I hadn't. So let's take a look at some of the more common and persisting questions from my article, and flush some more of the myths surrounding the decidedly-not-magic HDMI down the drain.

Is it true all HDMI cables are the same?
Forgive my bit of sensationalism in the title. Of course, two cables from different manufactures are likely to be physically different (though every cable company buys HDMI cables from only a handful of Chinese manufacturers). The picture quality, though, is going to be the same. Because of how the HDMI technology works, it's not possible for the cable to do anything to the picture but make it disappear. If the cable is defective, you're likely to get no picture or "sparkles," which look like white dots or snow. If you get this, return the cable; it's broken. If you're getting an image, it's exactly what your Blu-ray player or cable box is sending, 100 percent. There are images showing sparkles in the original article .

You talk about long runs of cable. I need to run 100 feet of HDMI cable through my walls to a TV in my bedroom. Are you really saying I only have to spend $50?
Well...sort of. I did some testing on cheap, long HDMI cables. The more expensive cables were more likely to transmit the data over long runs with a wide range of equipment.

Before a bunch of you say "HA! SEE!" let me explain. When the cheaper cables worked, they looked exactly the same as the expensive cables. It's just the expensive cables were more likely to transmit all the data. Some of the cheap cables would either have sparkles or not have any picture at all. Sometimes, they would work with some equipment, but not with others (i.e., one TV, but not another, or from one Blu-ray player but not another).

Regardless of what you choose, it is vital to test the cable before you run it through the walls. Even if you do, if you change equipment (TV, receiver, Blu-ray player), the cable may not work. It won't hurt to try a cheap cable from a place like Monoprice. If you want to set it and forget it, a better made cable may be worth the investment. Straightwire is worth checking out, as they make a decent cable (tested in my original test) and are delightfully free of the standard cable-industry hyperbole.

One possible trick, though, is if you're only running cable/satellite, you're only sending 1080i. All the cables I tested could handle 1080i easily. Even 1080p/24 is easily transmittable. It's 1080p/60 that's tricky. Thankfully, there are very few sources that are 1080p/60 (games, really, and some concert Blu-rays).

Whenever I look at HDMI cables at a store, they list data rates like "15Gbps." What is the difference between these data rates? Will I notice when using my Xbox 360 or PS3?
There are four types of HDMI cables for the home, and only four types:

  • High speed (Category 2)
  • Standard speed (Category 1)
  • High speed (Category 2) with Ethernet
  • Standard speed (Category 1) with Ethernet

Standard-speed HDMI cables are rated up to 1080i. They might do more than this, but they're just rated for 1080i. High-speed HDMI cables are rated well above 1080p, which is the maximum possible resolution from your Xbox and PS3.

Even 3D doesn't require more than what's possible over a cheap high-speed HDMI cable. Check out my article on "How 3D content works ."

You can buy a high-speed HDMI cable for a couple of dollars, so just buy that and don't worry about the rest. Check the HDMI Cable Buying Guide for more info on where you can get cheap HDMI cables.

You're an idiot!
You have no idea.

I bought an [expensive name brand -GM] HDMI cable, compared it to the one I got for free with my satellite, and there was a HUGE difference. You're an idiot.
Do you know that last guy? Interestingly, I also got letters saying the exactly opposite, that they bought a better cable, saw no difference, so they returned it. I see two potential possibilities.

The first is flawed testing. I recently did an article about the "Problem with A/B comparisons." If your testing methodology is flawed, you can get all sorts of weird results. Without being in the room, I don't know what you saw or how you tested it. Maybe you did see something, but it wasn't the cable.

There's also the problem of expectation. Having just blown $100+ on something, most people want it to work. So they'll see what they want to see. We all do this. The virulence of some of the comments on the original article were hardly surprising. People don't like being told they were wrong/got ripped off.

I was told I needed a special HDMI cable for my new 240 Hz LED to work.
Never buy from that store again. You were lied to, either maliciously, or by someone who has no idea what they're doing. Either way, avoid. The maximum resolution possible from any consumer equipment is 1080p/60 (which, as mentioned above, is rare). That 1080p/60 is converted by the TV internally to 120Hz, 240Hz, or whatever. All that's ever transmitted over HDMI is 1080p/60 from your Blu-ray player, or 1080i from your cable/satellite box, 720p from your Apple TV or whatever. Check out What is refresh rate? , What is 600 Hz , and Why doesn't my TV say 120Hz/240Hz? for more on this.

In theory if you have a home theater PC, it could output more than 1080p/60, and a High speed HDMI cable could transmit that higher resolution/framerate to the TV. But why would you want to? The TV, if it accepts that higher rate (it probably won't) will just convert it back down to 1080p/60, then up again to 240 Hz.

All HDMI cables can handle 1080i. High-speed (Category 2) cables are rated up to 4,096x2,160p24. In other words, even if you buy one the new Ultra HD "4K" TVs , your $2.50 high-speed HDMI cable is rated to carry all that resolution . I've tested this, and it the cheap cables worked perfectly.

Continue on to Still more reasons why all HDMI cable are the same , the HDMI cable buying guide , and 4K HDMI cables are nonsense .


Got a question for Geoff? First, check out all the other articles he's written on topics like HDMI cables , LED LCD vs. plasma , Active vs Passive 3D , and more. Still have a question? Send him an e-mail! He won't tell you what TV to buy, but he might use your letter in a future article. You can also send him a message on Twitter: @TechWriterGeoff.

About the author

Geoffrey Morrison is a freelance writer/photographer for CNET, Forbes, and TheWirecutter. He also writes for Sound&Vision magazine, HDGuru.com, and several others. He was Editor in Chief of Home Entertainment magazine and before that, Technical Editor of Home Theater magazine. He is NIST and ISF trained, and has a degree in Television/Radio from Ithaca College. His bestselling first novel, Undersea, is available in paperback and as an ebook on Amazon, B&N, and elsewhere.

 

Join the discussion

Conversation powered by Livefyre

Show Comments Hide Comments
Latest Galleries from CNET
10 mobile gadgets gone gonzo (pictures)
Apple in 2014: iPhone 6, iCloud hack, Beats and more (pictures)
The 12 most distinctive phones of 2014 (pictures)
Best mobile games of 2014
Nissan gives new Murano bold style (pictures)
Top great space moments in 2014 (pictures)