Japanese trains don’t honk when they leave the station. They play melodies instead. These melodies are called hassha merodi (“melody for train departure”). The melodies could be the jingles of popular anime, theme songs of popular movies, or the songs from old advertisements.
The melodies can also be specially made by composers. Minoru Mukaiya, one of the most famous melody composers, has composed melodies for over 100 train stations. He is so famous that people attend his concerts just to hear him play the melodies.
Train companies use the melodies as part of a psychological attempt to make commuters get on board quicker. It is assuring because commuters know the doors of the trains will not close while the music is playing. At the same time, it makes other commuters prepare for the arrival of the next train.