Apple MainStage 3 - Manual (Page 138)

Appendix A The Playback plug-in 138
Set the Sync mode for the Playback plug-in
When you add an audio file to the Playback plug-in, MainStage looks for tempo information in
the file. For audio files containing tempo information (including Apple Loops and files exported
from Logic Pro), the file is scanned for transients (short bursts of audio energy that usually occur
on rhythmic beats). Transient information is stored in the audio file and used to play the file with
the best audio quality, even when the file is played at a different tempo or pitch. For these audio
files, you can use the Sync feature to set whether the audio file plays at its recorded tempo or
uses the current tempo of the concert. When Sync is set to Off, the audio file plays at its recorded
tempo, regardless of the current tempo of the concert. This can be desirable, for example, when
the audio file contains non-pitched sounds or a sound effect. When Sync is set to On, the audio
file plays at the current tempo (set by the patch, set, or concert, by tapping the tempo, or by
listening to MIDI beat clock). This makes it easy to keep backing tracks, for example, in time with
each other and with your performance. Setting Sync to On can affect audio quality.
You set the Sync mode for an instance of the Playback plug-in from the Sync pop-up menu,
located in the lower-left corner of the plug-in window.
Note: For audio files that do not contain tempo information, Sync is set to Off and the Sync
pop-up menu is unavailable.
Set the Sync mode for a Playback plug-in
m To have the audio file play back at its original tempo: Choose Off from the Sync pop-up menu.
m To have the audio file play back at the current tempo of the concert: Choose On from the Sync
pop-up menu.
Choose the flex mode for the Playback plug-in
For audio files containing tempo information, you can choose between different flex modes for
playing back audio. Each flex mode is optimized for playback of a certain type of audio file, and
you can choose which flex mode an instance of the Playback plug-in uses to play back the audio
file you added. The available flex modes are:
•
Slicing: Slices the audio material at transient markers and plays each slice at its original speed.
Slicing is a good choice for general use, particularly for rhythmic material.
•
Rhythmic: Based on the time-stretching algorithm used for Apple Loops, Rhythmic is best
suited for playing non-monophonic material, such as rhythmic guitars, rhythmic keyboard
parts, and Apple Loops.
•
Speed: Time-stretches material by playing the source material faster or slower, including
changing the pitch. Speed is recommended for percussive material.
•
Polyphonic: Based on a phase vocoder, Polyphonic time-stretches material, delivering high
sonic quality with suitable polyphonic material. It is recommended for complex polyphonic
material and is good for all kinds of chords—such as guitar, piano, and choir—and for
complex mixes.
Because each flex mode can produce different results depending on the audio material, it is
recommended that you try out different flex modes for each instance of the Playback plug-in to
determine which provides the best playback for your audio files.