[Ne02ptzero]

> You can guarantee that you and someone else are listening to the same thing even across an ocean.

How can you guarantee that? NTP fails to guarantee that all clocks are synced inside a datacenter, let alone across an ocean (Did not read the code yet)

EDIT: The wording got me. "Guarantee" & "Perfect" in the post title, and "Millisecond-accurate synchronization" in the README. Cool project!

[moomin]

More, the speed of light puts a hard cap on how simultaneous you can be. Wolfram Alpha reckons New York to London is 19ms in a vacuum, more using fibre.

Going off on a tangent: Back in the days of Live Aid, they tried doing a transatlantic duet. Turns out it’s literally physically impossible because if A songs when they hear B, then B hears A at least 38ms too late, which is too much for the human body to handle and still make music.

[recursive]

It's a less hard problem than the duet. If the round-trip is 38ms, you can estimate that the one-way latency is 19ms. You tell the the other client to play the audio now, and you schedule it for 19ms in the future.

That's assuming standard OS and hardware and drivers can manage latency with that degree of precision, which I have serious doubts about.

In a duet, your partner needs to hear you now and you need to hear them now. With pre-recorded audio, you can buffer into the future.

[amluto]

> More, the speed of light puts a hard cap on how simultaneous you can be.

Special relativity does indeed have something to say about simultaneity.

> Wolfram Alpha reckons New York to London is 19ms in a vacuum, more using fibre.

And this is not, in any respect, a limit on simultaneity. If the endpoints are moving at very very very quickly relative to each other, then there are complications. Otherwise you measure that 19ms or so and deal with it.

[freemanjiang]

Haha yeah guarantee is a strong word. I just mean that it’s good enough to not be noticeable (even within the same physical room)