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A comment on Audiophile forum debating which versions of memcpy had the highest sound quality (2013). Parent comment

Re:Audiophile forum debating which versions of memcpy had th... by outworlder on Monday March 13, 2023 @01:22PM (#35139031)
> Never mind the fact that two devices connected with RJ45 ethernet have no direct electrical connection

> For the low, low price of $3800, you can be the proud owner of an audiophile grade, 100Base-T network switch

That buys you a seriously good piece of switching gear with 10GBe (or even higher) fiber optic links to whatever devices you could possibly want in a home. Heck, even a little over $100 buys you a switch with 4 SFP+ (Mikrotik CRS305).

I guess audiophiles will claim that the optical transceivers introduce latency and _they can hear it_

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Re:Audiophile forum debating which versions of memcpy had th... by acje on Monday March 13, 2023 @04:22PM (#35141942)
The absolute pain when the entire song is delayed by 10ns or what not. If only I could compensate by pushing play a little bit faster.
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Re:Audiophile forum debating which versions of memcpy had th... by eurasiantiger on Tuesday March 14, 2023 @03:31AM (#35148371)
The issue is not constant latency, but jitter i.e. latency is changing between bits
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Re:Audiophile forum debating which versions of memcpy had th... by Dylan16807 on Tuesday March 14, 2023 @04:13AM (#35148608)
Jitter matters in very specific cases in very specific pieces of equipment.

Jitter on the Ethernet transferring the file will have no effect.

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Re:Audiophile forum debating which versions of memcpy had th... by whstl on Tuesday March 14, 2023 @06:43AM (#35149528)
Like the sibling poster said, this won't cause jitter.

The audio isn't played directly from the ethernet packets. It has to be decompressed, decoded, buffered. In the end of it all the audio goes into a ring buffer and it is played very precisely by the sound card.

The playback itself is a hard-real-time process that needs time guarantees. Failure to fill the ring buffer by any reason can cause audible skips, but not jitter. But most players in practice will simply stop the playback.

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Re:Audiophile forum debating which versions of memcpy had th... by pezezin on Tuesday March 14, 2023 @07:40AM (#35149952)
The maximum jitter allowed by the IEEE specifications is 1.4 ns for 100-megabit Ethernet and 300 ps for Gigabit Ethernet. The bit time for a 48 kHz audio signal is ~20 000 ns. It is absolutely impossible that you can hear the Ethernet jitter.
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