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Comment by Jeff_Brown | Hacker News Reader

The figure of most interest to someone playing an electronic instrument is "tap-to-touch latency". The article indicates a minimum of 43 ms for that (28 round trip latency - 5 audio input latency + 20 touch latency). That's like ten times what you'd hope for.

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Emulators of old retro games also care about audio latency, as the emulated audio is generated on the fly by a turning machine, which makes it very hard to match visuals to audio if there is inherent audio latency.

I was very sad when I got a Galaxy Note (R.I.P. Note line) and Elite Beat Agents was unplayable due to audio lag. It makes sense, but it is a shame.

Damn, Elite Beat Agents was such a good game, I cried like a baby in the stage with You're My Inspiration.

If just matching is desired then you can just buffer video frames; all audio frameworks provide means to synchronize video and audio.

Of course, it probably makes the experience just worse if the delay is silly long..

By doing that you create input lag for the game.

The 20 ms tap-to-touch reference is from 2017, maybe this has gotten better in the past 4 years? But maybe not. And per the source, it's possible to get down to 10 ms round trip latency if you buy the right phone.

60Hz touch scan rate (16.67ms) was common in 2017, but now we can easily buy a phone with 240Hz(4.17ms) touch scan rate. It should be much improvement.

The article specifically says that tap to tone latency is typically around 20ms.

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In case of audio it doesn't really matter how fast the display updates though? Unless your numbers are for the digitizer and not the screen.

We're talking about tap-to-audio-output latency though, so it has nothing to do with display part of the screen.

And there is no "touch" on PC generally speaking.. input latency would be on mouse or keyboard.

I think you're talking different thing from the topic.

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