Apple Logic Express 9 - Manual (Page 1245)

MIDI Sync Preferences
The Sync pane contains the following preferences:
• All MIDI Output: Delay field: Delays or advances the MIDI output for all ports, allowing
you to compensate for any timing differences between MIDI tracks and audio or
(software) instrument tracks.
• MIDI Clock: “Allow to send Song Position Pointer while playing” checkbox: Song Position
Pointer (SPP) data is not normally sent while the sequencer is in Playback mode. (This
is in accordance with the MIDI Standard.) This option allows Logic Express to send SPP
data while the sequencer is running. The advantage is that external devices can also
follow Logic Express in Cycle mode. If your external devices cannot process SPP, you
should turn this option off. If your devices can follow MTC (MIDI Time Code), you should
leave this option unselected, and use the MTC functions of Logic Express.
1245 Chapter 43 Preferences in Logic Express