Comment by atoav

8 hours ago

One thing to realize is that especially for high resolution video cables these cheap testers can't really deliver. The way to test them is a eye diagram (see: https://incompliancemag.com/eye-diagram-part2/ ) and testers with that capsbility cost upwards of 10.000 Eurodollars.

13 comments

atoav

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jmalicki  8 hours ago

So you're saying there is something to audiophile grade HDMI cables?

  • scq  7 hours ago

    No. What it can affect though is the bandwidth of the cable, meaning e.g. for HDMI cables, they might not support higher resolutions or framerates. If it's on the border you might see random disconnects or screen blanks.

    The quality degrading is not something you will see, as it's a digital protocol.

    "Audiophile grade" HDMI cables are likely to just be a Shenzhen bargain-bin special with some fancy looking sheathing and connectors. I would trust them less than an Amazon Basics cable.

    • fmajid  7 hours ago

      Indeed. If I want super high quality cables, I get them from Blue Jeans Cables, who tell you exactly what Belsen or Can are cable stock and what connectors, as well as the assembly methodology.

  • HPsquared  7 hours ago

    With digital signals and ECC, the cable need only be "good enough" to get perfect data transfer through the system.

    • atoav  6 hours ago

      Correct. But especially if you're using long cables a cable with more "headroom" in the eye diagram will perform more reliable than one that is just at the edge of breakup.

      For home use that doesn't matter usually, but I for example run events where I need the cable to work also after 10 people stepped on it and then this can become a significant thing.

      Not in terms of quality, but reliability.

  • atoav  7 hours ago

    No. What I am saying is that it is hard to test the quality of a 8K 240Hz 4444 video cable without having a device that can send and receive this or even higher.

    If you send bits across a line fast enough you're grtting into the territory of RF electronics, with wrong connector or conductor geometry you will get echos on the line and all kind of signal loss. A good digital protocol should keep this at bay with error correction and similar mechanisms, but if you want to know what the good cable is on a better than binary scale of works/does not, you need to look at these things.