Using MIDI Pen ToolYou can use the MIDI pen tool in the track editor window when you want to edit a MIDI audio region. The tool is universal in that it does several different things in different parts of the editing window. You can access it in all views of track editor by pressing the Apple key on your keyboard.
Track Editor Window
Access the track editor by selecting your track and then clicking on the Track Editorbutton in the bottom left corner. The window will appear at the bottom.
Select View Type
Once in the track editor window, you can change the view of your audio region. Click on the View bar and scroll to the type of audio effect that you want to view or edit. In each of these views, the MIDI pen tool can edit the audio in a different way.
Notes View
In the Notes view, the MIDI pen tool can add, change or place a note anywhere on the notes grid.
Sustain View
In the Sustain view, clicking on the grid with the MIDI pen tool will quickly turn the sustain from Off to On at that point in the timeline.
Pitchbend View
In the Pitchbend view, the pen tool will add connecting points on the graph to control the bend of the audio pitch.