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Old 11-25-2009, 11:36 AM   #26
DarkStar
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Join Date: May 2006
Location: Surrey, UK
Posts: 18,016
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I think I may have found something (or at least this will prompt some ideas):

Have a look at this screenshot:
[IMG]http://img229.**************/img229/8539/r3141dsmiditiming01.th.png[/IMG]
Big pic:
http://img229.**************/img229/8...ditiming01.png

Steps:
-- I recorded some MIDI notes on track 2 AND Sent the MIDI to tracks 5 and 6 where I added an FX and recorded the audio all at the same time,
-- the recording on track 5 uses "Record Output (stereo, latency compensated),
-- the recording on track 6 uses "Record Output (stereo),
-- I then enabled the same FX on track 2 and used "Apply FX as new take" and "Explode all takes to new tracks", resulting in tracks 3 and 4,
-- I drew in some MIDI clips on track 1 for measurement.

Results:
-- the recorded audio output is 108 ms behind the MIDI,
-- the latency-compensated recorded audio is 36 ms behind the MIDI,
-- the audio from "Apply FX" is aligned with the MIDI.

Analysis:
For this trial, I had set my audio buffer to 18/18ms. The recorded audio output is 6 buffers adrift, the latency-compensated recorded audio is still 2 buffers adrift. Two buffers is equivalent to 1 i/o cycle.

Confirmation:
I set my audio buffer to 10/10ms and repeated the steps. The delays were 60 and 20ms respectively.

Conclusion
-- It look like it's latency-related
-- and the Record Output (latency-compensation) is not quite doing it.
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