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by mrob 2605 days ago
It's very disappointing that 300ms is considered "low" latency. The circumference of the Earth is 40075km, and the speed of light in optical fiber is slightly faster than 2/3rds of that in vacuum, so it's physically possible to send a signal to any place on Earth within 100ms, and get a reply within 200ms.

IMO "low latency" should mean low enough than it's very unlikely to be noticed, which most musicians seem to accept as 5ms. (Theoretically, even microsecond level delayed audio can be noticed if mixed with the original signal because of comb filtering.)
1 comments
gavv42 2605 days ago
I see your point.

Many audio streaming apps requires 1-2 seconds latency (especially on Wi-Fi), that's why I called the 100-300 ms range "low". 100ms is the minimum I've seriously tested on Wi-Fi so far. 300ms is, roughly, the maximum UI delay that feels acceptable (you press "play" and hear the sound).

I'll think about the wording..

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majewsky 2605 days ago
300ms is still noticably laggy when the audio is part of a video. Some media players can delay their audio to account for playback delay in the audio device, if the audio stack supports that. Does Roc support that, or if not, is it on your roadmap?
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gavv42 2605 days ago
> 300ms is still noticably laggy when the audio is part of a video.

Agree.

> Some media players can delay their audio to account for playback delay in the audio device, if the audio stack supports that. Does Roc support that, or if not, is it on your roadmap?

We have an open issue for implementing correct latency reports in PA modules. When we'll fix it, players that support that feature should automatically start taking the latency into account.

Thanks for reminding me, I'll test this feature specifically.

https://github.com/roc-project/roc/issues/171

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xorcist 2605 days ago
Many years ago we did some unscientific testing how latency affected a telephony application. Already at around 80ms there was measurable impact on the dialogue, with an increased frequency of the callers interrupting each other's sentences. Even modern VoIP applications can still be problematic in this regard and additional latency from the software stack wouldn't help.
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