User guide

Chapter 18 Editing MIDI Events in the Event List 473
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).
SysEx Events
System exclusive data (SysEx) is unique to individual MIDI devices. You can record these
events by using the dump utilities of your synthesizers. This enables you to save patch
information, or other data, outside of the MIDI device (in a Logic project or MIDI file).
The arrows in front and behind EOX are used to add or remove bytes.
Warning: Editing SysEx Events requires a thorough understanding of the data format
used by the MIDI device in question. Incorrect edits can lead to the corruption, or loss,
of sound or other data.