v10.8.1 BPM inaccuracy problem

[tyrebo]

Projects originated in pre 10.8.1 LPX, opened and worked on in 10.8.1, stems, mixes, bounces, are off tempo. When imported into a different DAW, or back into 10.8.1 LPX fresh project with exact BPM, meter, sample rates, they are off, and drift farther off over time of course.

I'll try building this project from scratch in a new fresh 10.8.1 project, but I'd like to get to the bottom of it, it will be a problem with several other older projects as well.

Appreciate any help, thank you

[oscwilde]

Maybe have a read thru this/linked topics and experiment?
It sounds like the project tempo and/or Flex etc. settings may be different between old/new versions of the app/projects.
Could also be plug-in delay compensation/audio buffer settings, etc. (there are under-the-hood differences in Logic 10.8.x versions, compared with earlier versions)....but your symptoms seem to indicate tempo-related issues.
Difficult to gauge where things may be coming unstuck for you without having the project.
https://support.apple.com/en-au/guide/logicpro/lgcp9281e70c/mac

[David Nahmani]

Could it be a sample rate mismatch? Are you sure you're reimporting them in a project file that has the same sample rate as the original audio files? 

[tyrebo]

12 hours ago, David Nahmani said:

Could it be a sample rate mismatch? Are you sure you're reimporting them in a project file that has the same sample rate as the original audio files? 

yes I've been very careful about that, and not all the tracks are audio, virtual instrument midi tracks too.

[tyrebo]

12 hours ago, oscwilde said:

Maybe have a read thru this/linked topics and experiment?
It sounds like the project tempo and/or Flex etc. settings may be different between old/new versions of the app/projects.
Could also be plug-in delay compensation/audio buffer settings, etc. (there are under-the-hood differences in Logic 10.8.x versions, compared with earlier versions)....but your symptoms seem to indicate tempo-related issues.
Difficult to gauge where things may be coming unstuck for you without having the project.
https://support.apple.com/en-au/guide/logicpro/lgcp9281e70c/mac

I'll look over that thank you, here's perhaps another description- 

First of all let me be clear, the “new” 10.8.1 project was created fresh in 10.8.1 with same settings as the old project- sample rate 44.1, BPM 94, 4/4. Then all the tracks were added from the old project with the file browser, some audio, some virtual instrument midi.

The “old” project was created around 2017, LPX version ?. But then newly opened in 10.8.1, it’s the one with time inaccuracy.

I output click only from both, you can see the start time is the same, the drift midway, and the clear difference at the 4 1/2 minute end, of about 5 seconds.

 

[David Nahmani]

5 minutes ago, tyrebo said:

I output click only from both

Both what? Isn't that the same project file?

[tyrebo]

2 minutes ago, David Nahmani said:

Both what? Isn't that the same project file?

no, the "old" and the "new" as described.

The screenshots are of the click bounces from the 2 projects, displayed in a new clean project just to show. Just describing all this, I create more confusion than I solve !!

[David Nahmani]

Ok so you said "Projects originated in pre 10.8.1 LPX, opened and worked on in 10.8.1, stems, mixes, bounces, are off tempo."  so I assumed you had only one project that originated in pre 10.8.1 and was opened in 10.8.1, further worked on and was now out of sync. 

So I'm not sure what 2 projects we're talking about. I mean how do you bounce the click from the 'old' project? Isn't that opened in 10.8.1? Do you still have an older version of Logic Pro? 

[tyrebo]

1 hour ago, David Nahmani said:

Ok so you said "Projects originated in pre 10.8.1 LPX, opened and worked on in 10.8.1, stems, mixes, bounces, are off tempo."  so I assumed you had only one project that originated in pre 10.8.1 and was opened in 10.8.1, further worked on and was now out of sync. 

So I'm not sure what 2 projects we're talking about. I mean how do you bounce the click from the 'old' project? Isn't that opened in 10.8.1? Do you still have an older version of Logic Pro? 

as I said I seem to be creating more confusion than anything else. I thought I described the new and the old. I'll have to try again after more coffee

 

[tyrebo]

7 hours ago, David Nahmani said:

Ok so you said "Projects originated in pre 10.8.1 LPX, opened and worked on in 10.8.1, stems, mixes, bounces, are off tempo."  so I assumed you had only one project that originated in pre 10.8.1 and was opened in 10.8.1, further worked on and was now out of sync. 

So I'm not sure what 2 projects we're talking about. I mean how do you bounce the click from the 'old' project? Isn't that opened in 10.8.1? Do you still have an older version of Logic Pro? 

An older LPX version would be helpful for this, but no I don't have one. Yes your interpretation of my explanation is correct and perhaps this will be clearer-

 

Project One- Originally created in 2017. Don’t recall what version of LPX. It includes audio tracks and virtual instrument midi tracks. It has now been opened in v10.8.1, some work done, stem and test mix bounces revealed slightly inaccurate BPM, too fast.

Project Two- Created new in v10.8.1. Identical BPM, time sig, sample rate as “One”. Then each track from “One” was “added” with the file browser. Stem and test mix bounces have accurate BPM.

The jpeg above is click bounces of each in a NEW test project just to show the offset. Top pair is start, mid pair mid song showing drift, bottom pair shows clear ~5 second offset at end of song.

I hope this clears things up.

I'll just proceed with Two, but I have several other older projects to continue work in 10.8.1. I am pondering some version evolution of settings that makes assumptions opening older projects.

Thanks for tolerating all this. T

 

[tyrebo]

19 hours ago, oscwilde said:

Maybe have a read thru this/linked topics and experiment?
It sounds like the project tempo and/or Flex etc. settings may be different between old/new versions of the app/projects.
Could also be plug-in delay compensation/audio buffer settings, etc. (there are under-the-hood differences in Logic 10.8.x versions, compared with earlier versions)....but your symptoms seem to indicate tempo-related issues.
Difficult to gauge where things may be coming unstuck for you without having the project.
https://support.apple.com/en-au/guide/logicpro/lgcp9281e70c/mac

I read through the info, thank you. They do seem to have complicated things for us with simple minds. However, "Keep project tempo" is selected, both versions, plugin compensation is on and buffer settings set in main prefs so cross-project. Should have been ok

[tyrebo]

further info- I found an old stereo mix bounce of the project, way before 10.8.1. BPM is accurate. All this seems to have to do with older projects opened anew in 10.8.1. Of course it could be pre 10.8.1, but this is when I discovered it

[David Nahmani]

Ok got it. I thought you were comparing two versions of the same project... which was what confused me. But never mind, got it now. 

So the project that is out of sync, can you open the tempo list and double-check that there isn't some odd tempo change that has crept in somewhere in there? 

[fuzzfilth]

One thing to specifically look for is whether there are any tempo *curves*. The calculation of these may have changed between Logic versions. Also these have a tendency to cause drift in certain situations.

Edited March 27 by fuzzfilth

[tyrebo]

 

David, not sure where I might find a tempo list, but scrolling the head from beginning to end shows no change in the control bar display throughout.

Fufilth(hah!) the tempo line is solid beginning to end with no automation points.

Thank you both for input, it remains a mystery. I'm encountering this again in another old project just newly opened

 

[David Nahmani]

39 minutes ago, tyrebo said:

David, not sure where I might find a tempo list, but scrolling the head from beginning to end shows no change in the control bar display throughout.

I'm not sure which display you're seeing, but for example the bars and beat display rounds up the values. To see the tempo list, at the top right of the main window, click the Lists button then the Tempo tab: 

[tyrebo]

2 hours ago, David Nahmani said:

I'm not sure which display you're seeing, but for example the bars and beat display rounds up the values. To see the tempo list, at the top right of the main window, click the Lists button then the Tempo tab: 

well there it is! I'd never opened that before. The project bouncing out too fast shows 94.2821, the project working properly is the correct 94, as set. How this happened at some point, I have no idea, nor how to correct it back to 94 as specified originally. At any rate, here's clear evidence of the problem finally, thank you. I was about to drop it as I'm the only one that seems to have experienced this.

[oscwilde]

3 hours ago, tyrebo said:

I'm encountering this again in another old project just newly opened

 

23 minutes ago, tyrebo said:

shows 94.2821, the project working properly is the correct 94

So is the offset the same in both projects that exhibit the behaviour?

[tyrebo]

no, a little different. Any new project originated in 10.8.1 shows no such discrepancy between the list tempo and the time/beats display, which is also the bpm specified there at project creation. Of course any bounces from those are fine. Only the older projects reopened, I'd have to open several more to see if it happens every time, but I hope to actually get back to work on the first one I reported here. Still of interest that older bounces from those projects are accurate. I just can't track when/what versions, this may show itself

[oscwilde]

14 minutes ago, tyrebo said:

Only the older projects reopened, I'd have to open several more to see if it happens every time

Jot down any discrepancies....just trying to figure out if this is a "consistent" offset (if it actually happens in all older projects) - possibly a percentage of the overall tempo? - as I'm assuming not everything is at 94 bpm 😉

[tyrebo]

I didn't know this, but in the tempo list the BPM shown can be selected and changed, corrected. Of course Locking/unlocking SMPTE Position of audio regions probably needs attention. So I can fix older projects that have to be opened in 10.8.1, but I still have no idea why this is occurring.

[David Nahmani]

9 hours ago, tyrebo said:

The project bouncing out too fast shows 94.2821, the project working properly is the correct 94, as set.

Well there you go. The discrepancy is because the LCD display gives you a rounded off value of the project tempo. So it displays 94 bpm but if you double-click that value you'll see the true project tempo value of 94.2821. It sounds like your project tempo should be 94 bpm so you can double-click the value and enter 94 again, which will set your tempo to 94.0000. See if that works? 

2 hours ago, tyrebo said:

I still have no idea why this is occurring.

Could it be that you've tried to use beat mapping or smart tempo at some point during your edits? 

[tyrebo]

9 hours ago, David Nahmani said:

Well there you go. The discrepancy is because the LCD display gives you a rounded off value of the project tempo. So it displays 94 bpm but if you double-click that value you'll see the true project tempo value of 94.2821. It sounds like your project tempo should be 94 bpm so you can double-click the value and enter 94 again, which will set your tempo to 94.0000. See if that works? 

Could it be that you've tried to use beat mapping or smart tempo at some point during your edits? 

I'll try that method too, changing it in the list worked as well.

The beat mapping/smart tempo question gets back to why this happened over multiple older projects. I've not intentionally used those tools. Slipping fingers, mystery shortcuts, and this football field trackpad can send me to mistake hell very quickly in LPX so it's possible, but it is too consistent. I always set the project BPM in the LCD display initially, why it changed remains a mystery. Thanks for the help, at least I can see the problem, and fix it in my projects.

[David Nahmani]

2 minutes ago, tyrebo said:

I'll try that method too, changing it in the list worked as well.

Yes indeed, same result. 

2 minutes ago, tyrebo said:

I always set the project BPM in the LCD display initially, why it changed remains a mystery.

From now on, either keep watching the Tempo list, or use a custom LCD display (click the down arrow on the right in the LCD display and choose Custom) so that you can constantly see the four digits after the decimal point and monitor your actual accurate tempo throughout your production process, and that way you should be able to tell at which point this error creeps in. 

[tyrebo]

On 3/28/2024 at 10:26 AM, David Nahmani said:

Yes indeed, same result. 

From now on, either keep watching the Tempo list, or use a custom LCD display (click the down arrow on the right in the LCD display and choose Custom) so that you can constantly see the four digits after the decimal point and monitor your actual accurate tempo throughout your production process, and that way you should be able to tell at which point this error creeps in. 

I'm marking this as a solution, not because the cause of the problem is revealed, but because the undo, after the fact, is here.