Join regions in the Tracks area
You can join untransposed audio regions, and join MIDI regions. Regions from audio Apple Loops, and audio regions that have been transposed, can’t be joined.
When joining audio regions, the regions must be adjacent to each other on the same track. If you join segments of compressed audio files, the files are converted to AIFF format. Audio regions are joined nondestructively. Logic Pro creates a new file for the joined audio (called a mixdown) that replaces the original regions. The new audio file is stored on your hard disk and is added to the Project Audio Browser.
Join one or more regions
Select the regions, then choose Edit > Join > Regions.
Join regions with the Glue tool
Select the Glue tool.
Do one of the following:
Select multiple regions by dragging, then click them with the Glue tool.
Shift-click regions with the Glue tool.
Join regions per track
Select the regions you want to join on each track. Shift-clicking, dragging to select, or Command-A may be useful for this step.
Choose Edit > Join > Regions per Tracks (or use the Merge Regions per Tracks key command).
The selected regions on each track are joined into a single region on that track. For example, if you select regions on four different tracks, and then choose Edit > Join > Regions per Tracks, a single region is created on each of the tracks from the regions selected on that track.
MIDI regions must be on the same track or on adjacent tracks. When you join MIDI regions, the joined region takes the name (and track) of the first original region. If the Transposition, Velocity, and Dynamics region parameters are different for the selected regions, they are normalized before being joined. (This means that all parameter values are written as data changes for each region. The parameters of the joined MIDI region are all set to neutral (default) values.)
If several (mono or stereo) regions on the same track are from the same original region, and in the same relative positions, no mixdown occurs. In this case, a single region is created.
No mixdown occurs when you join two regions on tracks that are panned to opposite sides, as the two resulting mixdown files would be identical to the original audio files (in the areas used for the regions).
If several overlapping audio regions on a track are selected, no mixdown occurs. You are asked to create a new audio file, which takes the name of the first region on the track. The selected regions are then mixed together, with no changes to volume, and without clip scanning.
Genuine mixdown with Clipscan
If you combine audio regions from two or more tracks, the current pan and volume values for the individual tracks define the pan and volume settings in the new audio file.
If you want to combine both sides of a stereo audio file (a mono channel on each of two tracks), first set the pan controls of the component mono sides to hard left and hard right, respectively.
Following the digital clipping scan (Clipscan) and completion of the mixdown, Logic Pro replaces the previously selected regions with one region that contains the entire mixed-down audio file.
You can use the Edit > Undo function (Command-Z) to restore the original audio regions, if you change your mind about the mixdown. If you do so, you are asked if you want to keep, or delete, the newly created mixed audio file. If you keep it, it remains in the Project Audio Browser, and can be further used and processed.
During a mixdown, the 32-bit resolution Clipscan function ensures that the highest possible level is maintained, without clipping.
Audio crossfades in Digital Mixdown
Digital Mixdown supports crossfades between selected regions.
The Crossfade parameters are defined by choosingLogic Pro > Preferences > Audio > General (or using the Audio Crossfade Options for Merge key command).
There are two faders:
Crossfade Time [ms]: The length of the entire crossfade. To turn off the crossfade, set this value to 0.
Crossfade Curve: To obtain a linear crossfade, set this value to 0. Other values (positive or negative), produce various exponential fades. The fade-outs and fade-ins are always symmetrical, to avoid deviations in level. The preset values are Time = 0 ms, Curve = 0 (linear).