The digital cable ripoff game
I created this article mainly to educate the consumer about a major scam they are likely to face when buying an HDTV and associated gear. Belkin, Audioquest and Monster Cable sell 6 foot long HDMI cables for $70 and up, when generic 6 foot HDMI cables are available for $13.
In this article I'm not talking about long cables such as those longer than 15 feet. Long cables, both digital and analogue, require special consideration to make sure that the electrical signal can pass reliably. Often you need a repeater or something in the mix to ensure that the signal stays intact. But this is the case for analogue or digital cables, its just a fact of any cables, they don't have unlimited range.
How we got here
For the whole of the 20th century, the standard cables for use with audio and video applications have been analogue. It wasn't until the very end of the 20th century that the consumer A/V market started to see products that had options for using digital cables. And now in the 21st century, we have one of the first A/V products that consumers must use a digital cable to use. An HDTV.
Probably around the 1980s with the advent of the Compact Disc, there began to be an interest in ensuring that the high quality of the audio signal coming out of the CD player degraded as little as possible by the time it hit the speakers. This helped push better cable technology that battled problems like interference from crosstalk and outside of the cable electrical sources. In this case we're talking about analogue cables, where the signal does not represent 1 or 0, but a wave. This wave can become distorted in the slightest way and suddenly by different from what was recorded to the CD. In audio the sound might not have the range of frequencies that it should. On a TV the picture might have some static or have color distortion. Thus, cables that used better conducting metals such as silver and gold or even cables that used special braiding where somewhat justified. Not always, but for the most part, it did make some difference.
Why digital cables are very different
Digital cables transmit the information of 1s and 0s. This is relayed by signal waves in the cables that are high or low. The thing is, there is such a large difference between what signals a 1 and what signals a 0 that there would have to be a major source of interference. As long as the cable is properly shielded, which even cheap ones are, it should be fine. The best solution of course would be to eliminate the source of interference rather than pay $100+ for a 6 foot cable.
If a digital cable where to start having a problem, you'd notice it right away. I know this from having bad cables in a computer system. In a computer, there are many digital cables running from the motherboard to the disk drives. When one of them breaks due to excessive wear, the cable becomes non-functional or starts corrupting data, then its not long before there are major problems.
You wouldn't spend $100 on a USB cable
What gets me about this whole digital video cable fiasco is that the computer industry has been using digital cables for pretty much its whole existence, but there has never really been a big market for high end cables costing many times more than the lowest price one. I've never seen a 6 foot USB cable costing more than $20. And if you think about it, quality of signal matters a whole lot more when you are talking about cables for transferring computer data. You wouldn't want that external hard drive that uses a USB cable to start corrupting data. Even if there are temporary problems with a cable, the protocols that computers and other digital equipment use allow for this by running checks on the data and retransmitting if there was an error. See Parity bit on Wikipedia for more information.
From what I've read, HDMI signals don't use a parity bit, but they do use an encoding at the physical level that reduced the total number of bit combinations to help reduce the possibility of errors.
Save your money, if you aren't offered a relatively cheap option for a cable for a digital connection, look online.