The Spiral of Silence theory (Elisabeth Noelle-Neumann, l973) suggests that highly consonant media content has a strong impact upon individuals' perception of the opinion climate as well as upon their opinion expression. Noting that the theory lacks empirical investigation, a study took advantage of a controlled media system in Cheongju, South Korea to examine the theory. Personal interviews of a cross-sectional sample of 287 adults were conducted covering a wide range of topics: interpersonal communication and mass media use, opinions, perceptions of opinion distribution on two social issues, and various demographic questions. Findings suggest that the consonance of media content and the influence of the mass media upon public opinion may have a curvilinear relationship. That is, as the degree of perceived consonance of media content increases, the media influence upon an individual's perception increases to a certain degree; however, if the degree of consonance exceeds the limit and if individuals notice a high amount of consonance, the influence of mass media on perception may become minimal again. (Six tables of data are included, and 34 references are attached.) (NH)