Custom sound notification on Google Calendar events
Setting up distinct alarms for separate calendars within the Google Calendar app--or for separate events on any of those calendars--is not a feature provided in the Google Calendar app. If you wish to have that function and to continue using the Google Calendar app, you'll need a third-party add-in such as Calendar Event Reminder. (CER)  That one costs a couple of bucks but there may be other options, perhaps even &quot;free&quot; apps.