6.0

The Event List
224
These event types are used to transfer MIDI controllers
(e.g. modulation, sustain, volume and pan).
Num
The number of the controller. All the various MIDI con-
trollers (such as the modulation wheel or sustain pedal)
have their own numbers (#1 or #64 respectively). Some
other effects are also defined, such as volume (#7) or pan
(#10).
Controllers that are defined in the MIDI Standard are de-
scribed in the Length/Info field.
Val
Value of the controller. Continuous controllers have a
range of 0—127. Switch controllers (#64—#90), transfer
only two states; off (val=0) and on (val anything between 1
and 127).
Aftertouch Events:
Aftertouch (or channel pressure) events are generated by a
mechanical pressure sensor beneath the keyboard. The re-
sulting sound modulation affects all the notes on that par-
ticular MIDI channel.
Num
This column is empty with aftertouch events, since they
have only one data byte.
Val
Strength of the pressure on the keyboard (0—127).
Poly Pressure Events:
Poly pressure events are generated by mechanical pres-
sure sensors beneath each individual key. The resulting
sound modulation affects only that particular note.
Only a few keyboards currently support this capability.
Num
MIDI note.