Right now, HDMI is the best way to connect audio and video. It's great for high definition displays and setups because it sends both audio and video over a single cable without any compression. HDCP, one of the newest digital transmission standards, works with HDMI (High-bandwidth Digital Content Protection).
There is one main problem with HDMI. It's too bad that it's not made for long cable runs. The signal is more likely to get worse when the resolution is higher and the length of the cable is longer. This is because the cables are made with pairs of very thin copper wire that are twisted together. Unlike normal coaxial cable, this one can cause interference and signal loss when used for lengths longer than 50 feet.
Luckily, the people who made the HDMI standard were smart and gave it a lot of thought. Because they chose to include a power line in the cable, repeaters that are inside the cable can now be powered. Signal boosters and repeaters usually need an external power source to boost the signal. However, HDMI can be extended without an external power source because of how it is made.
There are a few different kinds of these HDMI repeaters. There are HDMI cables that already have repeaters built in, and there are also plug-in repeaters that connect two HDMI cables and actively repeat the signal. A converter can also be used to change the HDMI signal into a signal that can be sent over a standard Cat5 cable. With this kind of system, there is a unit at each end of the cable run that changes the signal so that it can go over cat5 and then changes it back to HDMI at the other end.
If you need to be extra careful with your signal, you can also use outside power to power your HDMI repeater. This is a good idea because many HDMI sources just don't put out enough power to repeat the signal well. Even cables that have repeaters built in can often be connected to an outside power source. This just gives your signal a little more protection, and it may be a good idea depending on why you need the repeater.
Because HDMI is a digital signal, it can't be broken down too much before the picture and sound can't be understood. On analogue signals, the picture can get pretty bad before it's completely gone. On digital signals, a bad signal is always a bad signal. Even a small amount of signal degradation will cause you to see big artefacts.
For all your long cable runs, it's important to use a good repeater. Do some research to find out which type of HDMI extender—built-in, stand-alone, or cat5—is best for you. No matter what the problem is, you can probably find a way to solve it.
