Choose Window >
Advanced Tools. Click the MIDI tool , and choose Key Velocities
from the MIDI tool menu.
Select the region to be affected. Drag-enclose
to select measures, click to the left of the staff to select the entire
staff, or choose Edit > Select All.
Choose MIDI tool > Alter Feel.
The Alter Feel dialog box appears.
Enter the desired amount of key velocity alteration
(a positive or negative number) in the Downbeats By text box. The
range of MIDI key velocity is 0 to 127, so the number you enter here,
when added to the existing velocity values of the notes, can’t exceed
127. (If you like, click Percent of Original, and type a percentage value
into the Downbeats By text box.)
, and choose Key Velocities
from the MIDI tool menu.