Apple Logic Pro X - Manual (Page 877)

Chapter 25 Preferences, project settings, and key commands 877
When Additional Audio Options is selected in Advanced preferences, the following is
available:
•
Core Audio pop-up menu: Defines how your Core Audio hardware is synchronized to an
external timecode master.
•
MTC Continuous: Audio regions are started in sync, and the sample rate is continuously
regulated to match variations in the timecode master signal. Even very long audio regions
stay in sync in this mode.
•
MTC Trigger + Auto Speed Detection: Similar to MTC Trigger (see below), but the tempo of the
timecode master is constantly monitored while Logic Pro is running. The next time you start
Logic Pro, it will use an adapted sample rate. This mode keeps long regions in better sync
with the timecode master, although not as closely as MTC Continuous. It does, however, use
a constant sample rate, which is not affected by variations in the timecode master signal.
•
MTC Trigger: Audio regions are started in sync, but are then played at a constant sample
rate, regardless of any variations in the timecode master signal. Logic Pro always uses the
set nominal sample rate (44.1, 48, 88.2, 96, 192 kHz). This mode is suitable when it is vital to
retain the absolute pitch of a recording. If the speed of the timecode master deviates from
the nominal value, you may need to split long audio regions into shorter sections.
•
External or Free:Logic Pro has no influence on the sample rate. The audio hardware is
responsible for ensuring that the position and sample rate of audio regions match. This
mode is only advisable if you are sure that the Word Clock and timecode master are running
in sync—by using an external SMPTE or Word Clock synchronizer, for example.