HDMI cables have been the backbone of home entertainment systems for several decades. Although specifications continue to evolve to improve the bandwidth, they’re not without limitations—especially when it comes to transmitting over long distances.
While there’s no specific limit to the length of an HDMI cable, 50 feet is generally considered the maximum reliable length, and it’s rare to find HDMI cables longer than 25 feet. So what can you do when you need to run an HDMI signal more than 25 or 50 feet?
One often overlooked solution is to send HDMI signals over Ethernet cabling. Many smart homes and businesses already rely on structured wiring with high quality media distribution panels that can handle many Ethernet cables and HDMI as well. Now that long-run HDMI signals are becoming necessary for everything from digital signage in commercial settings, to advanced home entertainment systems that include multiple displays, structured wiring can solve the major issues.
HDMI Over Ethernet Extenders
The simplest (and most reliable) solution is to use HDMI over Ethernet extenders, which are adapters that convert HDMI signals to data that can be transmitted over Ethernet. You connect an extender to each end of your Ethernet cable, then plug in HDMI cables to each extender and voila.
The range offered differs from extender to extender but generally speaking they provide 200 to 300 additional feet of distance. These extensive ranges are possible, in part, because each extender is powered by its own AC adapter, so when planning your connections you need to account for providing each extender with access to an electrical outlet.
Cat 5e vs. Cat 6 vs. Cat 7
As any integrator knows, not all Ethernet cables are created equal. So what type of Ethernet cable should you be using for transmitting HDMI? The answer mostly depends on the quality of the HDMI signal you want to transmit. Technically speaking, you can use Cat 5e, Cat 6, or Cat 7 cables with most HDMI extenders. Typically though, it’s best practice to opt for Cat 6 or better.
To transmit 1080p HDTV signal over Cat 5, for instance, you actually need two Cat 5 cables and a dual extender. A single Cat 6 cable, by contrast, can carry a lossless 1080p signal all by itself. If you’re transmitting 4K or HDR video, you’ll need a Cat 7 cable.
Even if it’s only 1080p content that will be transmitted, Cat 7 might be the best choice. An HDMI over Ethernet setup is likely to stay in place for some time, so it makes sense to futureproof the installation from the outset.
Helpful HDMI Extender Features to Consider
Some, but not all, HDMI extenders include IR ports that carry the signals from a remote back to the source device. This is especially handy if a media player, for instance, is located 300 feet from the display or is completely out of sight.
Another feature to consider is PoE (power over Ethernet). Most HDMI extenders require AC power at both ends of the Ethernet cable but some can handle PoE. This means only the transmitting end of the extender would require power, critical when the receiving extender is inaccessible, such as behind a wall-mounted display.