Wiring Long HDMI Runs
HDMI is currently the best choice for Audio and Video connections. Because it transfers both audio and video on one cable, in an uncompressed format, it’s perfect for high definition displays and setups. HDMI is also compatible with the latest digital transmission standards like HDCP (High-bandwidth Digital Content Protection).
HDMI has one main drawback. Unfortunately it is not designed for long cable runs. The higher the resolution and the longer the cable, the more the signal has a chance of become degraded. This is because the cables are manufactured using twisted copper pairs of very small-gauge wire. Unlike normal coaxial cable, this makes interference and degradation a reality whenever dealing with lengths over 50 feet.
Fortunately, the wise creators of the HDMI standard thought long and hard about their specification. Because they choose to include a line for power within the cable, it has become possible to power repeaters that are internal to the cable. Normally, signal boosters and repeaters need an external power source to boost the signal, but because of it’s design, HDMI can actually be extended without an external power source.
These types of HDMI repeaters come in several varieties. There are cables with repeaters built in, as well as plug in repeaters that will connect two HDMI cables together while actively repeating the signal. A converter can also be used to change the HDMI signal into a signal that will travel over standard Cat5 cable. With this type of system, a unit is placed at either end of the cable run to transform the signal to go over cat5, and then transform it back to HDMI on the other end.
If extra care is needed for your signal, external power can also be used for your HDMI repeater. This is a good idea because many HDMI sources simply don’t output the power needed to do a good job of repeating the signal. Even cables with built-in repeaters often allow for an external power supply to be attached. This is just a little extra protection for your signal and may be a good idea depending on the situation in which the repeater is needed.
Since HDMI is a digital signal, it cannot be degraded much before the picture and audio is not longer decipherable. On analog signals, you can get quite a bit of degradation before the picture is totally gone. On digital signals, corrupt is corrupt, you will start to see major artifacts with only a little bit of signal degradation.
This is why it’s important to use a proper repeater for all your long cable runs. Do your research and find out which extender option is best for you: built-in, standalone repeater, or cat5 HDMI extender. No matter what the situation is, there is probably a solution that will work for you.