The amazing thing about GarageBand is the sheer breadth of features that lie dormant beneath its unassuming surface, not least of which is the ability to automate almost every parameter of every Software Instrument and effect plug-in it contains. With this it’s possible to draw control points on automation curves to set certain levels at specific points of the song that dynamically alter the value of their assigned parameters. This means that you can gradually increase the level of the reverb on a snare pattern, change the speed of the tremolo effect on an organ part, create a sweeping band-pass filter effect or program almost any other dynamically evolving effect you can think of. Here’s how to set it up.
Step 1: Choose your target
In your project, choose the track containing the plug-in whose settings you wish to automate. We’re going to use the AU Bandpass filter plug-in.
Step 2: Lane disclosure
Click the triangle button in the track’s header to reveal its automation lane. Each track already contains curves, but adding your own is easy.
Step 3: Add automation
Select Add Automation from the drop-down menu. This brings up a panel containing a list of the plug- ins currently assigned to that track.
Step 4: Check please
Click the triangles to reveal the checkboxes for all available automation parameters. Tick the box next to the parameter you want to automate.
Step 5: Reveal your curves
You can add as many parameters as you like. When done, click OK, then choose the parameter you just added to display its automation curve.
Step 6: Get the point
Click on the line to add control points. Start by adding an anchor point either side of the current value to avoid accidental changes elsewhere in the song.
Step 7: Reshape the curve
Move new control points vertically to alter the parameter’s value at that point. You can also reshape the curve by moving points horizontally.
Step 8: Copy and move
To move a set of points, draw a selection window around them, then drag the points off to the side. Holding down Option while dragging makes a copy.
Step 9: Link curve with region
Alternatively, choose ‘Lock Automation Curve to Regions’ from the Control menu. If you now copy a region, its automation data moves with it.
(Click on the image below to zoom in and view the annotations)