Apple Logic Pro 9 - Manual (Page 654)

To open the Piano Roll Editor as a separate window
Do one of the following:
µ
Choose Window > Piano Roll (or use the Open Piano Roll key command, default
assignment: Command-6).
µ
Drag the Piano Roll button, which changes to the Piano Roll Editor window as you drag
it.
Getting to Know the Piano Roll Editor
MIDI note events are represented by horizontal rectangles, aligned on a grid of horizontal
and vertical lines.
MIDI note event
• The horizontal placement of note events indicates their temporal (bar, beat, and
sub-beat) positioning within the region, and project.
654 Chapter 23 Editing MIDI Events in the Piano Roll Editor