Variation Model in a Cappella by Choral Class, Some Properties of Conducting in the Class of Choir and Choral Studies

Abstract

"A choir is a singing group performing vocal music with instrumental accompaniment or, a cappella." “The choir is a large vocal and performing group that, through the means of its art, truthfully, artistically fully reveals the content and form of the performed works and, through its creative activity, contributes to the ideological and artistic education of the masses. Variation (from Latin variatio - change, change) is generally called a kind of something, a slight change or deviation. The absolute indicators of variation include: the range of variation, the average linear deviation, the standard deviation, and the variance.