HDMI Cable Hookup Considerations
By: Phil Conner, Senior Editor
HDMI (High Definition Multimedia Interface) has quickly become the hookup medium of choice for both novice and professional home theater owners. HDMI offers a high bandwidth all-digital solution, which also carries both the digital video and audio signal. This simplifies hookup while increasing consistency in quality. There are a few important functionality considerations and specifications to be aware of when using HDMI in order to receive all of its advantages. Below is a run down of FAQs and factual information regarding the format.
Some key benefits of HDMI (esp. 1.3 specification)
- HDMI is the most future ready cable
- One cable convenience for digital video and audio
- Allows for two way communication for easy control
- PC compatibility as with DVI and RGB
- Higher Speed. The new 1.3 HDMI specification allows for transfer of up to 10.2Gbps of bandwidth. This increased from 5 Gbps.
- Deeper Color Information through higher bit rate transfer
- Lip Synch Correction (only in newer HDMI cables)
- Dolby High Definition Audio Format playback
Some other possible benefits are:
- Sharper motion on an HDTV due to faster screen refresh
What if I purchase a 1.3 HDMI cable today to work with a 1.2 compatible component that I previously purchased?
Not to worry. HDMI is backward compatible, meaning the newest generations of product will always work with older generation components (as long as there is an HDMI input or output port). There is one exception to this rule and that is when a component does not have DDC communication capability. This may be the case with some HDMI extenders and distribution amplifiers.
Are all HDMI Cables alike in quality (since they are digital) no matter what the price?
The shorter the HDMI cable length, the less quality and price play a part in the performance delivery of an HDMI cable. Conversely, the longer the length of cable, the more important quality becomes. Different qualities of HDMI cables have higher and lower error rates being transferred to the LCD TV, plasma TV or other digital display device. A higher data error rate HDMI cable will deliver a degraded (or non-existent) picture through a shorter distance cable. The higher the data error rates in an HDMI cable, the shorter the acceptable length of the HDMI cable. One aspect of quality to look for when purchasing an HDMI cable is the specification of the cable. The current spec to look for is v1.3 category 2. Then once you have found the current highest specification available at the time of purchase for an HDMI cable consider elements of quality such as thickness of conductors, silver plating, better shielding, quality of insulation, and internal engineering design. These quality differentiators make the difference in what we might call a standard HDMI quality and a super HDMI quality. They will also determine the run length and price of the cable.
Does the Length of an HDMI Cable affect output quality?
This is a great question because it is difficult to get a clear answer when interviewing cable and component manufacturers. As determined in the answer above, the short answer is yes. What’s known as the “cliff” effect (when the picture goes out entirely) occurs when the HDMI cable length has extended past the acceptable transfer range.
What is an acceptable length for an HDMI cable to dependably produce an excellent picture?
As mentioned above, quality plays a large part in this question. The larger and better the data rate (bandwidth) of the cable (pipeline), the longer the HDMI cable may be and still carry a good quality signal transfer. As a rule of thumb 3 meters should be the limit on lower quality HDMI cables. Stay with 2 meters if you can. Over 3 meters one needs to do some research into the quality of the HDMI cable. Some call their high end HDMI cables, Super HDMI. A few cable manufacturers are producing HDMI cables with a transfer range of up to 20 meters. Previously, the longest runs we could obtain were around 12 meters.
Must I have HDMI 1.3 cable to produce a 1080p signal from Blu Ray?
No, all of the HDMI cable specifications will carry a 1080p signal. However, you will need an HDMI output port on the output device and HDMI input port on the input device in order to allow for a 1080p signal. Other High Definition connectivity such as component or DVI will not work with a 1080p signal.