Metronome

From the Options menu, choose Metronome if you want the metronome to keep time while you're recording. When you start recording, the metronome will start playing at the tempo specified on the Ruler tab of the Project Properties dialog. For more information, see Setting project properties

To change the sounds used by the metronome, use the Audio tab in the Preferences dialog. For more information, see Preferences - Audio Tab

NOTE The metronome's sound is not mixed in the final rendering of the project.