This paper aims to analyze the history of announcement in trains in Japan and show the transformation of "how to speak/vocalize" and "how to hear/listen" by referring to resources such as newspapers, magazines and books that were written by "Ear-witness" all over the country.From 1920’s to 1950’s, radio broadcasting device for in-car announcement had been equipped with trains in Japan. Since then, it has been used for multiple purposes; letting passengers know its direction, name of the next station, side of the opening doors, encouraging them to have good manners inside a car, advertising the new products of railway companies etc... At the same time, it has caused disputes among people hearing it; some appreciating its convenience and courtesy as part of the new service, and others annoyed with repetitious, monotonous, wordy buzz of speech from overhead speakers. This paper, using the methods of media studies, reveals the history of in-car announcement and establishes the steps to examine the role of "miscellaneous broadcasting” in modern society.I first argue how publicity and communication in urban traffic are constructed in terms of sociology. Secondly, I illustrate changes of orality in both speakers (conductors) and listeners (passengers) through a comparison of broadcasting contents and reactions to them between before-and-after Privatization of Japan National Railways (1987). Finally, I clarify the relationship among three actors; train conductors, passengers and in-car announcement device in order to draw changes in body techniques (acquisition of the technique of “half-listening” in particular) affected by cost-efficiency-centered, laborsaving and service-oriented way of railway management after the Privatization.This is a study of “cultural noise,” or public sound by loud speakers, which has been paid minor attention to in modern Japanese soundscape.