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Is This HDMI Cable 1.4-compliant?
--A common question with a straightforward, but not simple, answer--
The Question, the Rephrased Question, and the Answer:
Ever since HDMI spec version 1.4 was published, one of the most common questions asked by our customers has been: "is your HDMI cable 1.4 compliant?" This question has always been a bit of a puzzler for us--not because the answer is a bad one, but because, for reasons we'll go into, that's not a question which our licensing agreement with HDMI Licensing permits us to answer as posed. If, however, the question is rephrased: "Is your HDMI cable fully compatible with all of my HDMI 1.4-compliant devices," the answer is, simply, "yes."
Our HDMI cables will support all features and protocols available under any specification version, including 1.4. That means anything--deep color, 3D, alternative audio formats and color spaces, 4Kx2K video, et cetera, et cetera. There is only one qualification to that point: if you need a cable that supports Ethernet over HDMI (which, at the moment, you don't; there are no devices we have yet seen on the market that use Ethernet over HDMI), you'll need to buy one which is specifically noted as supporting Ethernet (at this time, our 28 AWG Belden-based cable is available in a new Ethernet version, the Series-FE). But bear in mind that Ethernet support means only Ethernet support; Ethernet is not required to support any other HDMI protocol, feature, resolution, framerate, color depth, or what-have-you. Lately we've run into a lot of people who have been led to believe that Ethernet is required to support 3D, or to support other new features supported by the 1.4 spec; that's completely incorrect.
Why We Don't Just Call Them "HDMI 1.4 Cables"?
So, if the cable is compatible with HDMI version 1.4, and has been tested to meet the performance standards of HDMI version 1.4, why don't we just cut to the chase and call it "HDMI 1.4 cable" or "HDMI 1.4 compliant cable"? Well, HDMI is a registered trademark owned by HDMI Licensing, LLC; we are, as an HDMI Adopter, a licensee of that trademark, manufacturing products which carry the HDMI logos, and for that reason we try to stay compliant with HDMI Licensing's trademark usage guidelines, and those guidelines specifically prohibit the use of HDMI specification version numbers as a descriptive term for an HDMI cable. Accordingly, a cable may have been tested under HDMI specification 1.4; it may have been tested under the same standards applicable to testing under HDMI specification 1.4; it may have been certified compliant under HDMI 1.4; but it is not, despite any or all of those things, to be called a "1.4 cable."
At first blush, this may seem confusing. In fact, it's intended to be just the opposite. The problem with reference to version numbers in HDMI cable is that the use of version numbers creates a lot of false impressions and misunderstandings. For example, when HDMI 1.3 introduced new features, such as additional audio format support, consumers widely assumed that this meant that along with buying an HDMI 1.3 compliant DVD player and receiver which support these new features, one would need to buy a new HDMI 1.3-compliant cable. This was completely incorrect; but vendors certainly took advantage of it and used it to sell people new cables when the cables they already owned would work just fine.
What makes the use of version numbers even more confusing and useless to the consumer is that if it were proper to call something a "1.4 cable," that designation would still really be quite meaningless. Cables that were certified by the HDMI testing centers all the way back to the beginning of the HDMI specification would all qualify as "1.4 cables," because those cables remain compliant with all versions of the HDMI specification, including 1.4.
We are very much aware that many cables are being described by vendors as "HDMI 1.4 cables." This is misleading, and it is in violation of HDMI Licensing's trademark usage guidelines, but unless HDMI Licensing wants to take on a considerable campaign of litigation to enforce those guidelines it's likely to continue. It is not a good business practice, and when a vendor advertises using those terms it ought to be seen as a red flag; vendors who misdescribe one aspect of a product may misdescribe others, and are unlikely to be very knowledgeable about the product.
Why the Version Number is Unhelpful; What to Know When Shopping
Far from being highly version-dependent, HDMI cables have not fundamentally changed since the original version of the specification was published. The HDMI cable remains a 19-conductor cable which carries color channels and clock signals on four data pairs, and has a few other conductors for other functions. A cable made to meet specification version 1.0 is still a spec-compliant cable under version 1.4, so the implication which would be carried by representing a cable as a "version 1.4 cable" is misleading--the version 1.4 cable does not supersede prior versions, or support added features, and any cable, regardless of the version of the spec it was designed or tested under, is still compliant under 1.4.
Are all HDMI cables therefore the same? No, but version numbers aren't helpful in identifying the differences. There have been two relevant tweaks to the cable spec, which it is useful to know about. Although each of these changes occurred with a revision to the main spec document (first at 1.3, then at 1.4), however, both changes simply introduce optional characteristics to the cable, so the fact that a cable has been tested and deemed compliant under the applicable, or later, version of the spec does not in and of itself mean that the cable incorporates these changes--a cable which receives its testing approvals under version 1.4 may incorporate neither, either, or both of them. Consequently, even with these changes in mind the version number is of no help in determining what a cable's real characteristics are.
The first of these specification tweaks came with version 1.3, when the HDMI spec introduced the distinction between cable compliance testing for "standard" and for "high" speeds. According to new HDMI labeling guidelines, cables now are supposed to be designated as being "standard" or "high-speed" HDMI cables (also referred to, per the testing spec, as "Category 1" and "Category 2" HDMI cables). "Standard" speed cables are rated to handle bitrates up to 742.5 Mbps per data channel, which is the bitrate of a conventional HD resolution and framerate (720p/60 or 1080i/30) at 8-bit color depth. "High-speed" cables are tested to handle bitrates up to 3.4 Gbps per data channel, which is the maximum data rate allowed by the spec. What this means is that higher frame rates (e.g., 1080p/60), higher resolutions (e.g. 4K x 2K), deeper color (12 or 16 bit), or 3D video, applied to an HD signal (but not necessarily to a standard-definition signal) will push the bitrate into "high-speed" territory, where only a "high-speed" cable is certified to work. Other HDMI features, such as different colorspaces and audio formats, do not alter the total bitrate and so make no difference to the cable choice; likewise, faster display refresh rates (120Hz, 240Hz, etc.) are internal to the display and therefore have nothing to do with the bitrate in the cable.
So, when you're looking at a cable, the version number is irrelevant, but if you're planning to use the cable in a "high-speed" application, the distinction between standard and high-speed HDMI cable is potentially relevant. It should be added, though, that there is typically a good deal of performance headroom available, and a cable which is certified only for standard speed may work at high speed applications as well; there's no harm in trying, and failure generally is obvious: the screen will be peppered with bit-error dropouts if the cable isn't handling the bitrate well.
The second meaningful specification change came with version 1.4, when the HDMI spec introduced an optional "Ethernet channel" feature on the HDMI connection. This is the one and only feature in the HDMI specification which calls for a change in the actual physical structure of the HDMI cable (three existing, previously unassociated conductors have been organized into a shielded twisted pair), and again, the "version number" of the cable will tell you nothing about whether the cable incorporates it because a cable can lack the Ethernet channel and still be compliant with the 1.4 specification. Here again, the HDMI Licensing organization has called for the feature to be referenced on packaging: cables will either say "with Ethernet" or will not, to indicate whether the cable contains the Ethernet channel feature.
This Ethernet channel has been a source of considerable confusion, due to the misuse of version numbers to describe cables. The most common confusion we run into is that people associate the Ethernet channel with specification version 1.4 and proceed to the assumption that a cable, to support version 1.4 features such as 3D video, must contain the Ethernet channel. In fact, the two have nothing at all to do with one another. The Ethernet channel is not required to support any feature or protocol of the HDMI specification (1.4 or otherwise) other than use of the Ethernet channel itself. At this writing, in October 2010, we have yet to see a single device on the market which supports use of the Ethernet channel over HDMI; no doubt they will come along sooner or later, but at the moment there is no existing application for which the Ethernet channel is actually used.
In sum, there are now four kinds of HDMI cable in common use, none of which require a version number to identify: Standard HDMI Cable, Standard HDMI Cable with Ethernet, High-Speed HDMI Cable, and High-Speed HDMI Cable with Ethernet. All four types are completely compatible with HDMI specification version 1.4 as well as with prior specification versions.
Caveat Emptor:
As you will likely have seen when shopping for HDMI cables, many, many vendors routinely violate the HDMI trademark usage guidelines, calling their cables "version 1.4" or "HDMI 1.4 cables." For what it's worth, our experience has been that vendors who misuse the trademarks are, more often than not, completely ignorant of the compliant status of the product and of the most basic product attributes. If you want to be sure you're buying the right product, it's good to make sure that you're dealing with a vendor who actually knows something about it.
Beyond misuse of the "1.4" terminology, unfortunately, there are many misuses of the correct terms as well. For example, one prominent internet vendor of HDMI cable calls all of its HDMI cables which aren't "high-speed" "standard speed," when in fact many of those cables are not HDMI compliant even at standard speed. In 24 AWG cable, we have never seen a compliance certificate for a conventional passive cable longer than 40 feet; but conventional passive cables beyond that length are routinely claimed to be "standard speed" when they are actually not HDMI compliant at all. Now, a cable may very well function just fine beyond its speed rating and beyond its compliant length, in a particular application--for example, we have run 1080p video in our Series-1 cable with success for as much as 125 feet, five times the high-speed compliant length for that cable--but to claim that such a cable is compliant as a "standard speed" cable is certainly misleading.
It is easy to verify the compliant status of a cable: get the vendor to send you a copy of the Authorized Testing Center certificate showing the passing test result. Here are some examples of ATC certificates, for our coming-soon Series-FE 28 AWG HDMI cables, one showing a high-speed with Ethernet certification at 15 feet (the longest-length high-speed certification we have ever seen for a 28 AWG cable) and the other showing our standard-speed with Ethernet certification at 25 feet (the longest-length certification we have ever seen for any 28 AWG cable at any speed):
Series-FE Category 2 (High-speed) certificate, 15 feet
Series-FE Category 1 (Standard-speed) certificate, 25 feet
These ATC certificates are issued by Authorized Testing Centers which are independent from the cable manufacturers and vendors, and which have to be licensed by HDMI Licensing to conduct testing of HDMI cable products. If the certficate says a cable is compliant at high speed, or with Ethernet, or at a particular length, it is; if, on the other hand, the vendor cannot pass the ATC testing criteria, his cable is not certified compliant. Again, this does not mean that the cable necessarily will not work in some particular application--but the farther out of compliance the cable is, the likelier it is to fail in use.
Our Cables' Status, now and in Future:
We are currently in the process of replacing our Series-F2 cable with the Series-FE, which supports Ethernet, and soon we will be introducing Series-1E cables with Ethernet which will gradually replace our Series-1. The Tartan Cable products will follow at some point, likely beginning with the Tartan 24 and then the Tartan 28. The BJC Series-F2 cables are "High Speed" up to 15 feet, and "Standard" up to 25 (with the FE certified to the same distances, but with the Ethernet channel added) while the Series-1 cables are "High Speed" up to 25 feet (the longest of any cable on the market) and "Standard" up to 45 feet (also the longest of any cable on the market). The Tartan 28 AWG cables are "high speed" to 10 feet, "standard" to 15, and the 24 AWG cables are "high speed" to 20, "standard" to 40. All of these are fully compatible with HDMI 1.4-compliant equipment and will support all standards and protocols apart from the HDMI Ethernet channel.