Use Flex in Quick Sampler in MainStage
The Quick Sampler Flex parameters are used to synchronize the audio playback tempo. This is ideal for synchronously playing a melodic Apple Loop in a key that matches the key of other tracks in Logic Pro, for example.
The Flex parameters are found at the lower right of the Quick Sampler waveform display in Classic, One Shot, and Slice modes. Flex works for files with tempo information, including:
Apple Loops
Regions from the Logic Pro Tracks area
Bounced audio files
Files analyzed in the Logic Pro Smart Tempo Editor
Use Flex to synchronize an Apple Loop in Quick Sampler
Follow these steps to use Flex to play an Apple Loop synchronously with other tracks in your Logic Pro project.
Load a project with at least a few tracks.
Open the Loop Browser. Default key command: O.
Drag a melodic Apple Audio Loop, such as a rhythmic acoustic or electric guitar part, into the Quick Sampler waveform display. Drop it on the Original dropzone.
Play some notes on your keyboard over a few octaves. You will hear that the pitch of the loop changes, along with the playback speed.
Click the Flex button below the waveform display and play some notes on your keyboard over a few octaves.
You will hear that the pitch of the loop changes, but the playback speed doesn’t.
Start playback of your project and play a few notes on your keyboard.
You will hear that the pitch of the loop changes, but the playback speed isn’t synchronized with the project tempo.
While the project is playing, click the Follow Tempo button below the waveform display and play some notes on your keyboard.
You will hear that the pitch of the loop changes, and the playback speed is perfectly synchronized with the project tempo.
Tip: The Derive Tempo from Loop Length command in the Action pop-up menu calculates a tempo for the audio file based on the Loop Length. If using the Follow Tempo button does not yield the desired results, you can choose this option to calculate a revised tempo at which the loop is aligned to the beat.
As an option, you can choose a value in the Speed pop-up menu to divide or multiply the synchronized playback speed of the Apple Loop. Try this while the project is playing.
Tip: Flex Speed is also available as a modulation target.