Final answer:
Kangen is the strictly instrumental gagaku music inclusive of wind, string, and percussion instruments. It is part of classical Japanese court music and uses a variety of traditional instruments categorized by ethnomusicologists as aerophones, chordophones, membranophones, and idiophones.
Step-by-step explanation:
The strictly instrumental gagaku music that includes wind instruments, string instruments, and percussion is known as Kangen. Gagaku is the classical court music of Japan and has been performed at the Imperial court for several centuries. In gagaku, the ensemble of instruments typically includes aerophones such as the hichiriki and ryuteki, chordophones like the koto and biwa, and membranophones such as the kakko drum, along with idiophones like the shōko.
The shamisen, a traditional Japanese string instrument, often plays music in the background to enhance the scene's mood in different Japanese theatrical arts, but it is not traditionally part of gagaku. Instead, the shamisen is commonly associated with other forms of Japanese music such as the accompaniment for kabuki theatre.
To answer the additional questions: Kabuki differs from Noh because it is less stylized and makes more extensive use of elaborate stage devices and costumes. Izumo no Okuni, the founder of kabuki, first danced in the dry Kamo riverbed, which is located in Kyoto.
Finally, in ethnomusicology, a common classification system for musical instruments includes aerophones (wind instruments), chordophones (stringed instruments), membranophones (instruments with a membrane, such as a drum), and idiophones (self-sounding instruments).