Each project has a key, which defines the central note to which the other notes relate. By default, new projects are in the key of C major. You can choose a new key when you create a project, and change it later while you’re working. When you add Apple Loops to your project, they match the key of the project.
When Show Advanced Tools is selected in the Advanced preferences pane, you can also add key signature changes in a project. Key signature changes only affect the display of MIDI notes in the Score Editor—they do not have an effect on MIDI or Apple Loops playback. For more information about key signature changes, see Time and key signatures overview.
With the playhead at the start of the project, click the triangle on the right side of the LCD and choose Beats & Project, click the key, then choose a key from the pop-up menu.
In the Score Editor, double-click a staff between the clef and time signature, then choose a key in the Key Signature dialog. You can also drag the key signature from the Part box to the beginning of the project.
Click the Create Key Signature button in the Signature List.
When you change the project’s scale type from major to minor or vice versa, in some cases the key may change enharmonically (for example, from Db major to C# minor). These changes follow common practice for printed music, and affect only the key as shown in the menu, not the pitch of regions in your project.