These very expensive Ethernet cables claim to give you the best quality audio when streaming from your network storage to your computer. This is, of course, snake oil. $2 Ethernet cables will give you the same sound as $10,000 cables because they are digital. The music either arrives at your computer or it doesn't. You either hear it or you don't.
The best part about these cables:
"All audio cables are directional," says the product page. "Arrows are clearly marked on the connectors to ensure superior sound quality. For best results have the arrow pointing in the direction of the flow of music. For example, NAS to Router, Router to Network Player."
This would be hysterical if I thought no one would believe them. Ethernet cables aren't audio cables. They work exactly the same in either direction. They have to. Let's ignore that there is debate as to whether or not directional analogue audio cables actually make a difference. Let's ignore whether or not the Ethernet cable allows for a "stronger" or more reliable signal (louder 1s are better, right?). Let's focus solely on how digital audio is played.
Let's use a real world example. I have a recording of a Bruce Springsteen concert. The concert is broken down into one FLAC file per song. I want to listen to Thunder Road, which is 5m 56.705s long, and takes up 293,277,072 bits (36.7 MB). I want to stream that to my computer and play it out my speakers. Presumably, I want to listen to it at a rate of 1 second per second.
The computer won't play the song at the rate of the stream. If the stream is slower than 1 second per second, it'll either wait for more data before it starts playing, or it will frequently pause while the stream catches up. If it's faster, it will store the song in a buffer and play it at one second per second.
I have Gigabit Ethernet in my house, but let's pretend I have Fast Ethernet, which is 100 Mb/s (10 times slower). That means my song will take 4.89 minutes to copy into my computer's buffer. That's about 1.22 seconds per second. The entire song will arrive before it's done playing.
The reason I did all of this math was to demonstrate that no matter how the song gets to your computer, it's playing out of a buffer on your computer. The network transfer isn't transcoding the file to a different format, so it will play exactly the same whether it arrived on cheap cables, expensive cables, or wi-fi.
This is the first time I've seen something like this for network cables, but the scam has existed for years. It's most prominent in the HDMI cable industry. A $150 HDMI cable won't make your TV picture brighter or clearer. The signal is digital. The picture is either on your TV or it's not. At best, it will reduce signal loss over long distances, if you're plagued by that kind of thing.
Please, audiophiles, listen to this computerphile and don't buy overly expensive cables. It won't make the slightest difference. For sanity, I'm going to hope that all positive "professional" reviews of the Ethernet cable were paid for by the manufacturer, and are not the opinions of real people.