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Old 11-25-2009, 09:39 AM   #23
EricM
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Join Date: Jul 2009
Location: Ljubljana, Slovenia
Posts: 3,801
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Ok, I know I was experiencing this issue even with Cubase,
and I read back than that it is MIDI interface related etc.

But what bugs me as you guys is that while recording the data
is processed correctly by the VSTi, it's the recording of MIDI
data in sequencer that is wrong.

Did a bit of experimenting using Focusrite's Saffire LE SC
connected via firewire, using Saffire's native ASIO driver.
MIDI is received via MIDI cable.





I recorded the same note with one drumstick sample in reaSamploMatic
as Audio (green) and MIDI (red) at the same time, by foldering the VSTi
track and setting record: stereo out on folder track. I tried to hit
every second click as tight to the click as possible.

Than I also applied FX to item and put the audio to a seperate
track (yellow), to see the representation of the recorded MIDI
as audio.

Results:



This was the one I nailed most perfectly (see first and last track),
presuming the audio was recorded without offset.



As clearly visible, MIDI that was recorded is ~ 40ms (37 as measured
using tab to transient) before the audio recording, that was generated
with the same MIDI while recording.

Checking all the consequent transients reveals that the offset
is constant at 37ms (so it's not fluctuating, but it's just shifted).

Now, another seeming issue I found here is that while soloing the
VSTi track (still going to folder track, so with muted audio) and
ApplyedFX track with phase reversed does not null. Unfoldering
did not solve the issue, so it had to have occoured durring applyFX
stage. So just to be sure, I duplicated the Red MIDI track with
the sampled drumstick and MIDI data, phase inverted one, and they
null perfectly.

I was not able to null an applyFXed track with original VSTi in
any way (time offset, same volume, phase inverted) within Reaper.
So I tried one more thing. Rendered the VSTi track online to a
24bit 44.1 kHz wav, and did the same with phase inverted applyedFX
track, without changing the time selection.

Opened them together in AdobeAudition, mixed together, and imported
back in Reaper. This is the result:



Three of the events did not null, others did.

Any interpration of this is welcome.

e

Last edited by EricM; 11-25-2009 at 10:13 AM.
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