Apple Logic Pro 8 - Manual (Page 645)

Chapter 30 Advanced Tempo Operations 645
To manually define the maximum and minimum ranges of the tempo display, do
one of the following:
m Grab the maximum and minimum values in the tempo scale and drag them vertically.
m Double-click on either range value and type the desired numerical value into the text
field.
These user-defined values are displayed in yellow. If you want to return to the
automatic scaling mode, use the procedure described above, and leave the text fields
empty.
Switching Between Tempo Alternatives
The Alternative pop-up menu in the Tempo track allows you to switch between
different tempo maps. Put another way, you can create up to nine different tempo track
versions per project, and switch between them.
The original tempo track is automatically assigned to Alternative 1.
To create an alternate tempo map:
m Choose an unused number (2 through to 9), and create the desired tempo events.
This will be a blank tempo map, that contains one tempo event at the beginning of the
project.