HDMI & other digital cables - Isn't cheap as good as expensive over short lengths?
I’m researching my next surround sound system (probably a Denon AVR-3808 amp and Kef KHT2005 or KHT3005 speakers) and am thinking about the cables to connect it all. I can see the point in spending a fair bit on the speaker cables as they carry analogue signals which can easily degrade over distance.
I’m no technical expert but I’m rather more confused by HDMI and other digital cables. Looking at the review comments in the magazine, cables are compared for picture and sound quality. Of course, even digital signals degrade over distance. However, by the very nature of digital communications, a certain degree of signal degradation should not prevent a 100% perfect transmission of data. Beyond that level, the type of fault that occurs is to miss-read an increasing frequency of odd bits in the digital stream. This, I would have thought, would lead to the odd bum note in the sound track or odd glitch in the picture. Otherwise, for the vast majority of the stream, the picture and sound quality should be indistinguishable between cables.
Thus, I would have thought, it was possible to be quite objective about a digital cable’s ability to carry a 100% accurate transfer of data over various lengths (preferably in the adverse conditions of being wrapped by power and other cables as they will be in most home installations). That ability, of course, will also be affected by the quality of the plugs and ports to which the cable is connected at each end.
It seems likely to me, therefore, that even relatively inexpensive cables should provide 100% perfect connections over short distances and it is only worth spending more on these cables when longer lengths are required. Also, when the cable is less than perfect, it should manifest its shortcoming through occasional (or perhaps even frequent) glitches rather than a general reduction in quality. If you can’t notice any glitches then is that not good evidence that you have the best possible quality for your eyes and ears from your other equipment?
I may be talking total rubbish so I’d appreciate it if someone who knows better would put me straight. If not, then I’d like to see the magazine give more objective ratings for digital cables to know at what lengths it is worth spending more per meter.