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wiki:jack_latency_tests [2013/10/13 22:35] – [Measuring roundtrip latency with jack_delay] autostaticwiki:jack_latency_tests [2014/03/18 11:39] (current) – [Interpretation and Analysis] lgarrido
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   - It seems that for USB devices JACK //secretly// adds an additional period latency, but at most 1024 frames. This phenomena is not present with PCI devices.   - It seems that for USB devices JACK //secretly// adds an additional period latency, but at most 1024 frames. This phenomena is not present with PCI devices.
   - The latency reported by JACK is inconsistent.   - The latency reported by JACK is inconsistent.
 +
 +The first issue was explained by ALSA developer Clemens Ladisch in [[http://jack-audio.10948.n7.nabble.com/Differences-in-latency-between-USB-and-internal-audio-interfaces-td9071.html|this thread in jack-devel]]. The USB driver adds an extra period or a 24 ms buffer, whichever is smaller.
  
 Looking closer at these two issues: Looking closer at these two issues:
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 Alas, total latency measurement can not tell which it is. Alas, total latency measurement can not tell which it is.
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 ===== References ===== ===== References =====
  
wiki/jack_latency_tests.1381696523.txt.gz · Last modified: 2013/10/13 22:35 by autostatic