Timing issues in write mode

Benjamin Klum reporter

brummbear posted this in the forum as a response:

Hi Ben, Thanks for looking deeper into this! 1. You are right: It's overlapping items, not takes. 2. It does create timing issues because Playtime writes items that should not be there. I did a quick test to reconfirm this. As you can see in the attached screenshot multiple overlapping items were written. The full loops (upper 3 long items) should not be there since I released the pad. The "stairs" of short items are OK. The overlap between the last two short items can be explained by the 100ms rule that you described above.

I also confirmed that this ONLY happens if using Playtime's Write mode. Without Write there is no issue, i.e realtime play works just fine. Same if just recording the MIDI events and then letting Playtime create the items on the fly during playback or rendering does not cause problems. The issue is with writing items.

In a subsequent test I also recorded the MIDI input coming from Launchapd. Just to be safe I also set the sluggishness tolerance to 0ms in Playtime. My observations for Write mode were as follows:

a) MIDI events were correctly recorded, no overlapping issues here. b) The lag between MIDI event (Note ON) and Playtime writing the item on the timeline was constantly 20ms. Seems pretty long, but acceptable. c) The length of the item written by Playtime is always = length(MIDI note) + 200ms. E.g. MIDI note = 50ms => item written = 250ms, MIDI note = 500ms => item written = 700ms etc.

I found the last point interesting as I was expecting from your description the item to be just 100ms longer than the MIDI event.

Finally I also did a render from the MIDI events. The lag of 20ms and length +200ms were just like with items in write mode. No issue with overlaps as in write mode.

https://forum.cockos.com/attachment.php?attachmentid=30762&d=1492416788

2018-03-01T18:52:26+00:00

Comments (2)

Benjamin Klum reporter
Hi brummbear. I know what causes this: Whenever Playtime stops an audio clip immediately, it actually doesn't stop it immediately but adds 100ms more so the item fade-out can be applied by REAPER. Without this fade-out, you would most likely hear a click in live-playing. This fade-out is applied no matter if write mode is on or off.

So yes, this can definitely cause multiple overlapping items on several lanes! But it should not create multiple takes of one item. And it should not affect timing - the clip start and end times should be exactly the same as without write mode.

Now some questions:
1. In your case, was it really creating multiple takes? Or just overlapping items?
2. Does this really cause timing issues or were you just surprised by the fact that things overlap?
What I could do in case of such a quick repetition within the 100ms phase: Just writing the items side-by-side without any gap inbetween. But I don't want to invest time into that unless I know the current solution causes issues.
- 2017-04-16T13:06:14+00:00
Benjamin Klum reporter
brummbear posted this in the forum as a response:

Hi Ben, Thanks for looking deeper into this! 1. You are right: It's overlapping items, not takes. 2. It does create timing issues because Playtime writes items that should not be there. I did a quick test to reconfirm this. As you can see in the attached screenshot multiple overlapping items were written. The full loops (upper 3 long items) should not be there since I released the pad. The "stairs" of short items are OK. The overlap between the last two short items can be explained by the 100ms rule that you described above.

I also confirmed that this ONLY happens if using Playtime's Write mode. Without Write there is no issue, i.e realtime play works just fine. Same if just recording the MIDI events and then letting Playtime create the items on the fly during playback or rendering does not cause problems. The issue is with writing items.

In a subsequent test I also recorded the MIDI input coming from Launchapd. Just to be safe I also set the sluggishness tolerance to 0ms in Playtime. My observations for Write mode were as follows:

a) MIDI events were correctly recorded, no overlapping issues here. b) The lag between MIDI event (Note ON) and Playtime writing the item on the timeline was constantly 20ms. Seems pretty long, but acceptable. c) The length of the item written by Playtime is always = length(MIDI note) + 200ms. E.g. MIDI note = 50ms => item written = 250ms, MIDI note = 500ms => item written = 700ms etc.

I found the last point interesting as I was expecting from your description the item to be just 100ms longer than the MIDI event.

Finally I also did a render from the MIDI events. The lag of 20ms and length +200ms were just like with items in write mode. No issue with overlaps as in write mode.

https://forum.cockos.com/attachment.php?attachmentid=30762&d=1492416788
- 2018-03-01T18:52:26+00:00
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