You can always spend a lot on buying digital cables like HDMI only because some manufacturers claim their cables to be superior than the cheaper alternatives. Its justified if their claim is about analog cables like VGA (RGB) and audio cables where signal to noise ration is directly proportional to quality.
Better the cable, less the cross-talk, less the noise, better signal you get. But is it the same for digital cables like HDMI? Short answer, you DON’T need an expensive cable. Long answer: read on.
Signal Quality & Factors
HDMI & DVI use Transition Minimized Differential Signaling (TMDS).
Transition Minimized: The binary data (1s and 0s) at the source of a Bluray or HD box is not exactly the 1s and 0s your TV uses to create a picture. Before sending the signal out via the HDMI output, the 1s and 0s are optimized to minimize how many transitions there are. So instead of 10101010, the transmission may look like 11110000. Even though you might think the whole data is changed, its not hard to re-contruct the data at receiving end.
Differential Signaling: Each HDMI cable is actually multiple, small copper wires. Two versions of the data are sent over different wires. One of these is out of phase with the “real” signal. The TV receives all the data, puts the out-of-phase signal back in phase, then compares it to the “real” signal. Any noise picked up along the way will now be out of phase, and as such it is effectively negated and ignored.
This is exactly how Twisted pair in LAN networking works, there is no affect of external noise.
In digital world, either its all right or all wrong, no change of something in between. With HDMI signal, you either get everything and it’s perfect, or it isn’t perfect and you get nothing.
When there can be a problem
But there are scenarios where you’ve a long hdmi cable and you can have trouble in signal quality. If HDMI cable is faulty (this means one of the wires inside cable is broken) you would get white pixels.This a very rare scenario & is called Sparkles more like snow or sometimes static white pixels: image credit: cnet
Sparkles are not noise. They are failures that denote something is broken and you need a new HDMI cable.
No difference in Quality, whatsoever
But the thing to remember is that there is NO way that one HDMI cable would have “better picture quality” than another.
All the claims about differences in picture quality are remnants of the analog days, which were barely valid then and not at all valid now.
This is true for both Video & Audio, in fact audio has even better error correction, no way one cable is better than another.
Types of HDMI Cable
There are only 4 types of HDMI cables:
High Speed (also called Category 2) 1080p with or without Ethernet, and Standard Speed (Category 1) 1080i with or without Ethernet.
There is no difference in 100hz, 120hz, 200hz, 240hz cable. Its only 4 types of cables that we already mentioned. Everything else is a marketing gimmick. You don’t need a new HDMI cable for 3d, its all fake.