Use beat mapping on MIDI regions
You can beat map MIDI regions to adjust the project tempo so that freely recorded notes in the regions align with beats in the ruler.
Apply beat mapping to MIDI regions
Select the regions that you want to use for beat mapping.
A representation of the selected regions appears in the Beat Mapping track.
Tip: You may want to zoom in to work more precisely.
In the Beat Mapping track, click the first (leftmost) ruler position that you want to associate with a MIDI note.
A vertical line appears at the clicked ruler position.
Drag the bottom part of the line so it aligns with the beginning of the note you want to map to the ruler position.
The line adjusts to match the beginning of the note. If the Tempo track is displayed, a Tempo change appears at the ruler position.
Logic Pro automatically inserts a tempo change, which appears in the Tempo track.
Moving from left to right, beat map the subsequent notes in the selected regions, repeating the same steps.
To connect a ruler position to a position in the region where no note exists, hold down Control while drawing the connecting line. This allows the line to snap to any subdivision, even where there is no note event.
To erase a beat mapping, double-click it with the Eraser tool, or select it and press the Delete key.
To erase all beat mappings, click anywhere in the header of the Beat Mapping track (except on the controls) to select all data in the track, then press the Delete key.
When using the Delete key, be careful not to accidentally delete other selected events or regions.