MIDI notes off on grid

[Electrohermit]

I'm creating drum patterns in Protools LE 5.3 using the PT Midi track. The notes are sent to a Kurzweil board and then recorded to 2 audio tracks. I have the PT buffers set to 128 and level 1 for least delay, however Ive noticed that when I look at the MIDI notes on the grid, and compare them to the recorded audio tracks, the MIDI notes are exactly 1/16 of a note behind. In other words if I look at a tom hit on the audio track and look at the note above on the midi, there is a 1/16 shift. There is no delay if I monitor the MIDI notes live with the audio track I just recorded. So apparently its not delay. They both play in SYNC. Could this be a DISPLAY issue? I'm probably overlooking something since the shift is exactly 1/16 off. I can live with this, but when I go back to fool around with the MIDI notes, its hard to compare it to the audio drum track. Thanks.

[Electrohermit]

Looks like I just discovered the cause, for anyone who wanders through this post. Midi global offset in the preferences window. For some reason PT comes with the default set to -5000. Which is basically a pain the arse DIGI, because my system had no real lag, and now all of my audio tracks are sync'd to a drum track that is 5000 samples off. Best to ship with that sucker set to 0 and let us discover the lag on our own, I think. phwwwwwwww. I guess I'll set it to 0 and shift my drum track using the shift command.

[Roy Howell]

ddavismedicalart,
The thing about Midi Offset is that different Midi devices have different degrees of midi latency, and this is outside of PT itself. In other words, my Korg module has an average of about -2000 samples of latency, but Reason has virtually none. PT gives you the option of adjusting midi latency either Globally (Global Midi Offset....ALL midi tracks together), or individually (using Midi Track Offset under 'Windows'). The Global Midi Offset is fine if you're only using one midi device, because the latency amount is the same. But when you use say, 2 or 3 different midi devices with varying degrees of latency, Midi Track Offset (individual) is best to use.

So, if you're only using one midi device now(the Kurzweil), and you know that the latency is -5000, I would just set Global Midi Offset to that. But if you add other Midi devices or soft synths(like say Reason or Sampletank) to what you're doing, you would want to adjust the latency individually under Windows/Midi Track Offsets.


I hope that helps.
-Roy

[albee1952]

Here's another variation that supports Roy. I use a Roland TD-10 v-drum kit for recording. I start by recording midi and a left&right stereo track. If I send midi back to the TD-10 module and record again, the resulting audio is behind about 1600 samples. It takes time for the midi to trigger the sounds. I end up moving the midi 1600 samples forward and then track the midi-driven module to 8 channels of drums that line up fine. I discard the earlier stereo drum audio track.

[Electrohermit]

Thanks Roy and Albee. YOu know, I did read the DIGI manual from start to finish really good, but I guess I just got sidetracked. When I saw the notes off, I just assumed the worst. Then It dawned on me to go and check the manual and voila. I did exactly what you guys suggest. I simply recorded the notes and compared the audio to the midi and adjusted the offset until it was just right. I have a Korg Z1 also. Seems that a pre-delay of -700 did the trick. I went back and shifted all of my audio tracks LATER by 4300 samples (the default was at -5000) and everything was peachy. Very quick to fix, thank god. Im just glad I caught this before sending my session to the engineer. That would have been embarrassing! This is like the pilot who forgets to put the landing gear down.

[underbiteman]

Sorry to dig up an old post but I also had to go back and read the manual for the Midi Offset. It suggests setting the offset equal to the buffer setting because if you don't midi will playback later than the audio track by that amount. But isn't the audio track delayed the same amount by the buffering also?
I'm mostly using Reason by the way.

[Electrohermit]

hmmmm, I think I understand what youre saying under, but keep in mind that in my particular situation I was recording drum (and bass) tracks. Drum (and bass?) tracks are considered critical timing tracks and should be recorded only when the buffers are set to the minimum, 128 samples and 1. But if youre not recording drums or bass or other foundation tracks, then you of course would go up to say 256 samples and 2 HWB, which is what I usually work at anyway after criticals are laid. So I think any MIDI tracks after that would indeed have some delay from just inside the PT rig. But then again I think the solution is simply to zoom in on say about 10 notes and loop just those. Record them and compare the MIDI note on one track to the AUDIO track just below it (hide all other tracks) and then simply keep re-recording just that area and adjusting the offset say from -700 to -800, until the notes line up exactly above and below, or more precisely until the very tip or start of the notes align. Thats a good point you bring up. I never actually recorded any more after my drums and bass, but if I do I'll be sure to watch out again if I change the buffers. I think the bottom line is to just set everything up, MIDI, buffers, tracks, FX, etc and then after all that is done, be sure to do a short test of a few notes and adjust offset until they match.

[Electrohermit]

Just a friendly REMINDER to anyone using MIDI and browsing this post. BE SURE to check that your
H/W BUFFER SIZE and DAE PLAYBACK BUFFER are set to the lowest settings possible when your editing, or recording MIDI.

I recently recorded some drum and bass MIDI tracks, ate some dinner, farted around,,turned the BUFFERS up high again, then went back to edit some MIDI and chased my tail around for hours trying to figure out why it didn't sound right. Actually, it sounded so bad and off I was utterly thrown.

It wasnt till the next morning that I realized I had FORGOTTEN to turn DOWN the buffers again when going back to fool with the MIDI notes. When songs are nearing completion you will want to listen with the PLUGINS and all the tracks with a high level of BUFFER. But if you go into a MIDI track to fool around, set those buffers low again!