Mastering the Piano Roll Editor
Zoom into individual MIDI notes and edit pitch, timing, length, and velocity directly — the tool that turns a rough take into an exact performance.
The Piano Roll is where Software Instrument recordings stop being "whatever you happened to play" and become exactly what you want. If you've recorded any MIDI in the Beginner track, this is the natural next step.
Opening the Piano Roll
Double-click a Software Instrument or Drummer region, or select it and open the editor panel from the bottom of the window. You'll see a grid: time running left to right along the top, pitch running bottom to top down the side (lower notes at the bottom, exactly like a real piano turned sideways). Each note you played appears as a small rectangular block.
Reading a note block
A note block tells you three things at a glance:
- Horizontal position — when the note starts
- Horizontal length — how long the note is held
- Vertical position — which pitch it is
Click a block to select it, and its details often show in a small info readout so you can confirm exactly what you're editing.
Moving and resizing notes
- Drag a note left or right to change when it plays.
- Drag a note up or down to change what pitch it plays.
- Drag the right edge of a note to change how long it holds.
- Drag to draw in a brand-new note directly on the grid, without needing to play it on a keyboard at all.
Fixing timing without quantizing everything
Sometimes only one or two notes are actually off — dragging just those, slightly, onto the beat is more musical than blanket-quantizing a whole performance (covered in the next lesson), which can strip out feel you actually wanted to keep.
Editing velocity
Most Piano Roll views include a velocity lane below the main grid, showing how hard each note was played as a small bar. Taller bars are louder/harder notes. Dragging these up or down changes dynamics after the fact — useful for bringing out a melody note that got buried, or softening a stray note that jumped out too loud.
Working with chords
Notes played at the same time stack vertically at the same horizontal position. Select multiple notes at once (drag a selection box around them, or Shift-click) to move or transpose a whole chord together without disturbing its internal shape.
What's next
The Piano Roll gives you direct control over individual notes. The next lesson covers GarageBand's automatic timing and dynamics tools — quantization, velocity scaling, and transposition — for fixing a whole performance at once.
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