This year after the Beatles' performance in Japan in June 30, the groups began to sing while playing musical instruments such as electric guitars will debut one after another in Japan. In response to this, the youth entertainment magazine "Weekly Meisei", began to collectively call these groups and music "Group Sounds" or "GS", and the name became widespread. There are several theories. There is a theory that Takeshi Terauchi said that in 1965 when asked about the genre of Blue Jeans at that time, "It's a group sound" and "But it's a singular form, so Group Sounds is better".