Logic Pro (X) Punch-ins butchered when Flex Time'd


I confess I’ve been composing this inquiry in my head multiple times in hopes it will be understandable but as brief as possible. Good luck, right?

PREFACE: I have a piece in development comprised of 3 movements, each movement with a corresponding increase in tempo applied at a specific point in between – 152, 155 & 160 BPM.

All subsequent instrumentation will be built on foundational audio tracks of guitar and bass. To play the guitar and bass parts cleanly, I recorded them at 140 BPM, (and set this as the project tempo). I expected to make the tempo changes globally using Flex Time. And it was working.

I recorded both instruments in Movement I in a single pass and in a single region respectively. I moved on to do the same in Movements II & III. I entered the tempo changes in global, and was happy to hear the piece shift gears at the assigned places.

However, the passages in II & III were more complex, and I made some errors. So – back to 140 BPM again – I corrected these with a series of punch-ins using auto punch, (which works really well; some were a measure or two in length, some were but one brief note).

I played the entirety with all 3 Movements still at 140 BPM, and was satisfied with the completed punch-ins. Then with flex enabled on the appropriate tracks, I input tempos 152, 155 & 160 per Movement, and sat back to enjoy. Movement I played perfectly, (there being no punch-ins), but in Movement II, when the punches rolled thru, all hell broke loose; actually, all synchronicity broke loose, and the guitar and bass parts were chopped into unrecognizable bits while the virtual drums played on perfectly. Ah, drummers… The same thing happened with the punch-ins in Movement III. However, once beyond the punches, it all came back together and ended correctly as written.

I backtracked, setting everything back to 140 BPM, and opened each take folder to view the punch-ins, and they all appeared as they should. But after I reset to 152, I studied them again, and things were obviously out of whack large. There silent spaces where there shouldn’t be. Most telling – although I have yet to understand the exact significance – the ‘mini-regions’ representing the punches were partially greyed out, always the last third or so of the waveform.

I then thought that maybe each punch-in had to be treated as an individual new recording or region, so I selected each and manually toggled flex enable off and on again. But this made no difference.

To add to my confusion, I noticed that not all the punch-ins are so affected. Both the guitar and bass had a long note/chord p.i. struck at the very end of the piece and allowed to diminish, and that p.i. was not partially greyed out – seemingly (?) because it wasn’t being forced by the tempo increase into a smaller ‘space’, as it had no boundary on one side. What’s happening here? Is this like trying to put a big foot in a shoe that shrunk?

So I’m trying to learn what I did – or didn’t do – to create this situation, and/or how to correct it or circumnavigate it in the future. I vary recording tempos and final playback tempos, and use punch-ins, as a regular and reoccurring part of my production process.

I had the project tempo set to ‘Adapt Tempo’, even while making the recordings. Should it have been otherwise?

There are 7 sub-settings for Flex Time. What should I be using?

If anyone could shed some light on this, I would be greatly appreciative.

Just a thought and a simple one at...
As a test, complete a Save AS of your project in a state where it performs as expected, at 140bpm?
Next, in this saved as version, select regions per track that have a punch in and use Bounce in Place with the Destination>Selected Track option check on.
Once this step is completed for each track, proceed with Flextime and tempo changes.
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Thank you kindly, CSeye.

I am trying to do what you described.

But for 'Bounce Track In Place', I am offered to check boxes: 1. 'New Track'; 2. 'Replace Track'; (as well as 3. 'Bypass Effect Plug-ins'; and 4. 'Include Volume/Pan Automation'. ['Include Instrument Multi-Outputs' with drop-down box: 'As Additional Tracks' is greyed out.])

So, regarding choices 1. or 2., I'm unsure as to which equates with 'Selected Track'.

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What I described above was the result of selecting a specific region with a punch in and then right-clicking to select Bounce and Join>Bounce in Place. Selected track is an option here.

File menu>Bounce>Regions in Place is designed for one track at a time, or merging several tracks into one track, also presents the Selected track option.

If using Bounce Tracks in Place, which allows you to bounce several selected tracks at one time, then use the Replace Track option. Just be aware that you'll need to adjust the project end time to close to the actual end of the regions, otherwise Logic wastes times scanning empty track space until the designated end of the project.
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You are right, and the procedure DID indeed restore my butchered punch-ins when run thru the tempo change(s).

How great it is to have the benefit of someone with knowledge and experience to come up with (what CSeye referred to as) a ‘simple thought’ – especially for relative newbie like yours truly. And to take the time to try to explain. Large thanks. I aspire to have my own such simple corrective thoughts in the future, but I’m a long way from such fluency in Logic. (And I realize I need to study ‘bounce’ in its myriad forms.)

The reason I missed the mark on my first attempt was that I opened the take folder – in this case the punch-in take folder – and selected individual punch ‘mini-regions’. Wrong. Must select the entire region, inclusive of the afflicted punches. I went with the right-click>Bounce Regions In Place; I will mention that initially, by default Mute was pre-selected for the source, so you need to choose ‘Leave’ or, of course, you won’t hear it.

Hope this helps somebody else down the line. As previously stated, varying the recording tempo and the final playback tempo is a regular and reoccurring part of my production process, and truth be told, I live by my punch-ins. Now I know what to do when the confluence of the two jump the track.
:jammming: [...< a Lefty!]

Thanks, CSeye.

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Now I know what to do when the confluence of the two jump the track.
It's really good to hear that the recommendation proved useful for your advanced production process.

Your initial description of the issue was clearly written and understandable. The key detail for me was that the flexed tempo changes were working before punch-ins entered the picture. Once I understood that, the need to bounce to make intact regions was clear. Regarding Bounce, you now have options: the right-click method for a punch-in here and there, and the File menu options if there are multiple edits on a single track or on several tracks.

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