Everyday (in rural Japan at least) there is a music played over loud speakers at certain times of the day.
7am – time to wake up
12pm – Midday
5pm – time for kids to go home
The music varies during the day and varies from region to region. I’m guessing it’s a relic from the days when it helped farmers keep track of time in the fields.
The 30 second chime becomes a part of everyday life that keeps you in sync.