The standard nagauta ensemble consists of singers, an equal number of shamisen, and the hayashi ensemble of the Noh. The flute player often doubles on the bamboo flute (Takebue or shinobue). Since nagauta music originated in the Kabuki theater,many offstage(geza) instruments may be used as well. Such additions are usually inspired by meanings in the text or its mood. The jo ha kyu terminology of noh is used in modern nagauta studies as well. Modern Japanese scholarship has also coined the term Kabuki Dance form to provide a basic for analyzing the structure of individual pieces. The six basic sections of the form are the oki, michiuki, kudoki, odori ji, Chirashi, and dangire (or dangiri). These sections are often identifiable by conventions of style or orchestration. “The same is true for many sections in a noh drama. Such tendencies are important to both traditions since their music is through-composed;that is, the progression from one section of a piece to the next is not based on tonal or thematic relations. There are no first or second themes that can be traced throughout a piece as in a Western classical composition. Thus the sonic clues of sectional change in Japanese music are important to the sense of logical progression through musical time.
Reference; William P. Malm Six Hidden views of Japanese music
University of California Press