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All HDMI Cables are the Same! Or are they… – Full Test | HD Guru - Part 4373
All HDMI Cables are the Same! Or are they… – Full TestMarch 30th, 2011 &
& , , , , , , A few months ago we ran a story where I said that there was . I still stand by that. Most cable companies are so incredibly misleading in their marketing/advertising it borders on outright lying.Others just lie.So we decided to put a test together to see if there really was any difference in cables. The results were… interesting.The Plan We gathered seven cables from four manufacturers/retailers, all over 50ft. Why over 50ft? Because the differences are going to be more pronounced than over shorter cables. Also, short HDMI cables, even the most horribly made ones, are highly likely to work just fine. In fact, I have yet to see a short HDMI cable that didn’t work.A Bit of Background The industry standard methodology is using a test pattern generator and a waveform monitor. That’s all well and good, but we felt that a “real world” test would give more useful results, showing what problems arise in actual systems. Turns out, there’s a lot.There are four basic items in play when you’re trying to get an signal over HDMI from one place to another. The first is the source. There is a tiny transmitter in each source component that attempts to send a signal out along the cable. It’s not very powerful, but it is fairly robust. Presuming it has enough power to do its job (not a given) they work pretty well.The next step is the cable itself. HDMI cables are actually made up of several individual tiny copper wires. The quality of the metal and gauge of the wire varies greatly, and both affect how well the signal from the transmitter can travel along the cable.In the display, there’s a receiver that, well, receives the signal. At this point, presuming there’s enough signal to read, it gets decoded.Resolution is the final factor. 1080p requires twice the bandwidth of p. This is why, as you’ll see in the testing, everything passed 1080i, but not necessarily 1080p.If you want some more technical details, I talk about the . &Not Better than, IS or ISN’T This is the most important fact in this article: An HDMI cable either works, or it doesn’t. If it doesn’t, you’ll see it, have no doubt. What you’ll see, though, is not a softer image, or more noise. These are what happens to an analog signal when it degrades, not a digital one. With HDMI’s digital signal, if not enough of the data is received by the TV, you’ll get: sparkles, partial image, blank screen, and of course your TV saying there is “no signal.” I saw all of these in my testing.Sparkles is perhaps the most insidious of the bunch, as the rest of the image looks fine, but random white dots appear on the screen. This was generally severe enough for anyone to go “wtf?” but on a few occasions, it was fairly mild. Still enough, though, that one would notice it and want a better cable. Even if it was mild, this still registered as a “fail” in my testing. Heeeeeeeeeeeeere’s some sparkles:To a lesser or greater degree, these are “sparkles.” White spots that look like snowflakes. Or dandruff. This is what a signal looks like that’s staring down the precipice of total signal failure. You can’t see it in this small picture, but the rest of the image on the TV looks just as detailed as it did using a cable that actually worked. It was as if it had started snowing inside the TV.With the fails, there’s either no image, or an unwatchable image (flickering, etc). In all these cases, the cable is faulty or inadequate, and you should return it for a different cable.So when a salesman says “this will give you a better picture” he is either lying, or doesn’t know what he’s talking about.The Test I used a Panasonic Plasma, a Samsung Plasma, a Sony LCD, and JVC and Sharp projectors. All were current or last year’s models. For sources, I used , Toshiba, and Sony Blu-ray players. The Oppo and Toshiba were also put through a Marantz receiver that merely switches (no upconverting). Lastly, I used my AT&T U-verse Motorola VIP1225. Early in the testing process I also used Apple TV and , but as even the worst cable was able to pass these signals, I stopped testing them.The source breakdown is like this: &#p/60
– 3D (Avatar BD)
&#p/24 (Avatar BD – not tested on the Sony as it wasn’t a 3D TV) Toshiba BD &#p/60 Sony BD &#p/60 Marantz Receiver w/ &#p/60 Marantz Receiver w/Toshiba BD &#p/60 U-verse &#iSource material was a mixture of real video and test patterns, all from Blu-ray. Each display was tested with each source on its primary HDMI input and its “last” HDMI input (#4 in the case of the Panasonic and Samsung, #2 for the JVC and Sharp). If there was a discrepancy between these two, the remaining inputs were tested. The Sony, having two on the back and two on the side, occasionally had odd results, so each of its inputs were tested each round.Each cable/signal was given a reasonable amount of time to sync up, though it was usually pretty clear very quick what worked and what didn’t. The image (when there was one) was inspected at close distance for any sparkles or other artifacts (which predictably, there weren’t).All cables tested had “High Speed” on their jackets, though some were labeled “Standard Speed” on their company’s website. The difference is that “High Speed” is supposed to pass at least 1080p.One final word on this testing methodology. Technically, a cable could pass 1080p, but still not conform to the full definition of “High Speed” or “Category 2” cabling, which requires successful transmission of much higher resolutions. As none of these higher resolutions are in any current or future video spec, this is sort of irrelevant.*****PLEASE NOTE***** In no way is this a test or indictment of the products used for testing. These are meant to be a sampling of available gear, not “Product A doesn’t work with Product B.” That is a completely different article.Key: Red=Fail Green=Pass * = SparklesMonoprice 2678 – 50ft ($53.32)Right off the bat, we’re got a compelling case for cheap cables. This is a $53 cable, listed as “Standard Speed,” yet passes 1080p just fine. No issues whatsoever. We might as well just stop here.Monster Cable Monster MC 1000HD-50 – ?,? 50ft (MSRP: $499.95, ) So here’s the question. Like the Monoprice 2678, the 1000HD passes all signals to all the gear. Yet it’s 4x the price. Also, the 1000HD is decidedly one way. If you swap the cable ends, you get nothing. Odd for a passive cable. Overall build quality between the two was about the same, with the Monoprice cable being a little thicker, but the Monster having a better jacket and “feel” of connector. One thing in the Monster’s favor is that their plug was very grippy, locking into the HDMI connector on source and display more solidly than most other cables. Is this worth $250? No.Straight Wire Super HDMI Cable – 52ft (MSRP: $400)The Straight Wire cable has a built-in signal correcting circuit (as did two of the longer Monoprice cables). Like the Monster and 2678, it performed well in testing, though I got an odd fail with the Marantz/Toshiba combo.Straight Wire told me to flip the cable around (“backwards” from what the instructions said) and it worked fine. So I listed them as pass for everything. There are several “no-name” 50ft HDMI cables on Amazon, but this one claimed to be 1080p and &# Gbps” which implies High Speed (also known as Category 2), even though these words weren’t specifically mentioned.As you can see from the chart, performance was pretty terrible. It works with some gear, but fails completely with others. I’d be curious what Amazon’s return rate is on this cable. I have several short no-name Amazon cables, and they work fine.One odd result is worth noting. On the Panasonic with the Oppo at 1080p/60, inputs 1 and 2 worked, but 3 and 4 didn’t. This is possible on many products, as the quality of the HDMI receiver isn’t always consistent across different inputs. I have been told something as simple as the length of the internal wiring from the connector to the chip can have an effect. The Samsung had the opposite problem with the Marantz/Oppo pair, failing on input 1 but passing on 2, 3, and 4.If you are frustrated that the cheapest HDMI cable didn’t work as well as the more expensive models, I feel your pain.Monoprice 7697 -75ft ($47.70)Like the Straightwire, the 7697 has a signal correcting nubbin. There’s an 8-position dial on the top to help you fine-tune performance. The fails listed in the chart were where no setting garnered a picture. Some gear required an adjustment of the dial, others didn’t. Of those that did, some would only work in one position, others, several.These cables are clearly labeled for use in one direction, and only work as such. Overall performance was very good, with only the Panasonic/Toshiba 1080p causing an issue on input 1 and 2. The Oppo at 24p was even stranger, as 3D and 60p require far more bandwidth, yet those passed.Monoprice 2894 &#ft ($76.23)Most cable manufactures will tell you that a passive 100-foot cable shouldn’t work at all, never mind working with 1080p. Yet here it is. Performance wasn’t great, with the Sharp not really getting anything, and the Sony and Panasonic not liking the Oppo. Still, for a ridiculous length of 100ft, and costing only $76.23, it’s worth trying the 2894 to see if it works with your gear, if you need this kind of run. If you do, this cable will likely be going through walls or something, so PLEASE test the cable before you put it in the wall.Monoprice 7698 &#ft ($57.00)For a little less money, the 7698 has a signal correcting nubbin, like the 7697, but is a thinner gauge than the 2894.Performance was actually a little better than the 2894, trading the Samsung/Marantz for the JVC and getting a few more sources to work with the Sharp.Subjective As I discussed above, it’s not possible for one cable to look better than another. It either works and you see 100% of the signal, or it doesn’t work and you get nothing, sparkles, snow, or flickering. But, there were going to be people who would freak out if I didn’t give these cables a subjective component as well. These people (cable manufacturers) claim that certain HDMI cables look and sound better than others.Now this is bull when it comes to video, but with each cable I looked for any increase in noise, or decrease in resolution, using actual video and test patterns. You can accuse me of bias all you want, but if I did see a difference, that would be a fascinating story so I was looking for it. The cables that worked all looked the same. Surprise surprise surpriseBut audio… Now this is a little more complex. It is next to impossible for there to be any difference in audio when playing back Dolby or DTS codecs (of any resolution). This is due to how these formats are encoded and transmitted.It is, however, at least theoretically possible for there to be an audible difference with PCM. This is due to the amount of jitter with HDMI, which can vary depending on manufacturing quality (true of any digital cable). There is so much conflicting data on this, I think it warrants its own article. So look for that in the near future.In the mean time, use the decoder in your receiver instead of the BD player and you should be fine.Conclusions In all, I was rather surprised by the variety of performance among these long cables. Even so, our standard recommendation stands:Buy the cheapest cable you can. If it works, you’re good to go.That said, we have to add some caveats. Just because the cheap cable you buy works now with your current gear, doesn’t mean it still will if you replace your BD player, receiver, or TV. That much is very clear from the testing, there’s a lot of variety.From this survey, the more expensive cables really were more likely to work on all the gear with different bandwidth signals. As frustrating as this is for all the deal-hunters out there (myself included) it does offer a “buy and forget” option for those that don’t want to worry about it. For those of us where $50 and $400 is a big difference, the cheaper cables are a fantastic deal, when they work. As long as you can return the cable if it doesn’t work, there is no risk in getting the cheaper cables. Even if in a year you get a new BD player and the cable no longer “works,” buying a new one will still save you $200 in the long run over the more expensive cables.The fact is, below 50 feet, performance is going to be a LOT more uniform. In other words, you’ll have more cables that will work on everything. As such, it’s even more likely that a cheap cable will perform the same as their more expensive counterparts. At short distances (under 10 feet), like we’ve always said, there’s not going to be any difference.The most important thing to remember is if you’re running HDMI through your wall, test it first!!! Also make sure it’s rated to match your local building codes.&?Geoff Morrison – Follow me on Twitter
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