Apple Logic Pro 8 - Manual (Page 450)

450 Chapter 18 Editing MIDI Events in the Event List
This allows you to address the different sound banks (preset, internal, card, and so on)
of connected MIDI keyboards and modules. The synthesizer must be able to recognize
controller 32 as bank select, but unfortunately this standard is not used by all
manufacturers.
If you have any problems with bank select, check your synthesizer’s manual to see
whether, and how, it responds to bank select commands.
Note: You can change the type of bank select messages sent by Logic Pro (see
“
Defining Custom Bank Selects ” on page 887), if necessary for your devices.
Aftertouch Events
Aftertouch (or channel pressure) events are generated by a mechanical pressure sensor
beneath some MIDI keyboards. These events can be used to modulate the synthesizer
sound. All note events on a particular MIDI channel are affected. This means that
applying pressure to one note in a held chord will affect all notes in the chord.
 Num(ber): This column is unused, as aftertouch events only have one data byte.
 Val(ue): Displays the amount of pressure on the keyboard (0 to 127).
Poly Pressure Events
Poly(phonic) pressure events are generated by mechanical pressure sensors beneath
each individual key on some MIDI keyboards. The resulting sound modulation only
affects the particular note that is pressed harder (after the initial keystrike). Only a few
keyboards offer this capability.
 Num(ber): Displays the MIDI note name (C3, G4, and so on).
 Val(ue): Displays the amount of pressure on the key (0 to 127).