Apple Loops in Logic Pro for iPad
Apple Loops are prerecorded musical phrases or riffs that you can use to easily add drum beats, rhythm parts, and other sounds to a project. These loops contain musical patterns that can be repeated over and over and can be extended to fill any amount of time.
When you add an Apple Loop to a project, a region is created for the loop. When the project plays, the region plays at the project tempo and key signature. This lets you use several loops together, even if the loops were recorded at different speeds and in different keys.

Logic Pro has four types of Apple Loops:
Audio loops (blue) are audio recordings. You can add them to audio tracks and edit them just like other audio regions in the Tracks area and Audio Editor.
MIDI loops (green) can be viewed and edited, including individual notes, in the Piano Roll Editor. You can change the sound of the instrument plug-in used to play the loop. You can convert MIDI loops to audio loops by adding them to audio tracks.
Session Player loops (yellow) contain genre and parameter settings that you can change in the Session Player Editor. You can convert Session Player loops to audio loops by adding them to audio tracks.
Pattern loops (violet) contain all the notes and pattern information from a pattern created using Step Sequencer. Pattern loops can be edited just like other regions in the Tracks area, but the notes themselves can be edited only in Step Sequencer. You can convert pattern loops to audio loops by adding them to audio tracks.
In the Loops view of the Browser, you can find loops with the instrument, genre, and feel that are right for your project; preview loops; add loops to your project; and create a selection of your favorite loops.
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