Voice classification in non-classical music chart that follows. The ranges given below are approximations and are not meant to be too rigidly applied. Some men, in falsetto voice or as a result of certain rare physiological conditions, can sing in the same range as women. These do not fall into the female categories, instead called countertenors within classical music. Within contemporary music, however, the use of the term "tenor" for these male voices would be more appropriate. Teaching voice within non-classical music is an emerging field. Up to this point, voice teachers and voice research have been largely concentrated with classical methods of singing. However,
The Singing Voice of Japan The Singing Voice of Japan The singing voice of Japan (, "Nihon no Utagoe" / うたごえ運動, "Utagoe-undō") is the name of a social and political movement that emerged after World War II in Japan and based on musical and choral activities of the working class of the entire nation. On the ideological position of communism or democratic socialism, activists of the movement organize choral circles in factories, in schools and in their residential areas. The movement reached its peak in the years 1950–60. Japanese singer Akiko Seki () is generally regarded as the founder of the Singing Voice of Japan.