If all HDMI cables are basically the same design, pinout, etc. how have they been able to double, quadruple, etc. the bandwidth on them over time?

Question

Going from HDMI 1.4 to 2.1 there is a 5x increase is bandwidth. Is it because the cables themselves were never the issue but it was the connectors/chips in the devices themselves that couldn’t handle it?

I know part of it is the actual quality of the cables themselves and tighter tolerances, more twists in the wires, material purity, etc. but I can’t imagine that alone would be enough to fully account for this.

In: 565

Answer 1

This is the same as ethernet cat5/cat5e/cat6 cables.

A cables jacket can only say what specificstion it was tested at. Not what future options exist. There are lots of tiny adjustments that are made over time that do make differences to the upper performance level, wire guage, plug connectors, twisting etc.

A well made over engineered old cable may well meet new specifications if tested, a cheaply made enough to pass may not.