Logic Pro X: Time stretch regions in the Tracks area
When you resize regions, the position of notes and other events in the regions does not change. Alternatively, you can time stretch regions to shorten or lengthen the relative distance between events in the regions. Expanding regions increases the distance (the amount of time) between events in the regions, while compressing regions decreases the distance.
For example, you can make a region play in half time by stretching it to twice its original length, or play in double time by shortening it to half its original length.
You can also time stretch individual notes, chords, and other items in audio regions using Flex Time. For more information, see Flex Time and Pitch overview.
Time stretch MIDI regions
Option-drag the left or right edge of one or more MIDI regions.
The events within the region are stretched or compressed, proportionately, by the amount that the MIDI region is altered in length.
Time stretch or compress audio regions
Option-drag the right edge of an audio region.
This action stretches or compresses the audio by the amount that the region is altered in length, and replaces the original region with a new PCM audio file (in the original file format, or AIFF, if the original was not PCM).
Time stretching is limited to the value of the current Tracks area grid setting (in the Snap pop-up menu).
Choose the audio time stretching algorithm
Choose Edit > Time Stretch > Time Stretching Algorithm, then choose an algorithm from the submenu.
Universal (default): This high-quality algorithm is able to handle any kind of audio material and is generally recommended for most time-stretching tasks. The following two algorithms can, however, deliver better results in cases where the audio material exactly matches the outlined specifications.
Complex: Choose this algorithm to obtain natural-sounding results when time-stretching complex musical material—orchestral music or final mixes.
Percussive: Perfectly maintains the timing of rhythmic material, making it a good choice for drum loops and percussive, nonharmonic signals. In comparison to the Beats Only algorithm, the Percussive algorithm is better suited for percussive material that has been processed through a reverb (or contains a long tail). This may also apply to percussive playing styles, such as staccato electric piano or clavinet parts. Beats Only may be the better alternative for dry drum recordings.
Version 5 (Legacy): Inherited from Logic 5, this algorithm can be used on most types of audio material. It imparts a particular color on processed audio, which may be a useful creative option.
Any Material (Legacy): Can handle most types of audio material.
Monophonic: (Legacy) A specialized algorithm for monophonic material—an individual voice, or brass or woodwind instrument, for example.
Pads (Legacy): Use on polyphonic material with harmonic content—choirs or string sections are good examples.
Rhythmic Material (Legacy): Use on rhythmic material—can be drums and percussion, but less obviously rhythm guitar, clavinet, and piano comp parts.
Beats Only (Legacy): Perfectly maintains the timing of percussive material. This algorithm should be your first choice for all kinds of dry drum loops.