This particular video is on the Japanese Noh style of music. There are some distinctive classical consistencies and elements in Japanese music. This particular clip is taken in Tokyo.

http://www.youtube.com/watch?v=Klww4AerPgw

The music overall has pitches that differ from Western pitches and tones. These can be heard throughout this clip, although not all are tones different from the Western tones. These tones that differ are called semitones.

The tempo seem to quite fast for Japanese music which is generally slow in nature and almost nonpulsatile in sounding, but the Japanese Noh style clearly has a moderate speed.
Other Elements of Japanese music is a sense of space between the notes, known as a ma. This allows the listener to get a sense of balance and equilibrium.

One particular thing that can be noted is the stage room. The performers are playing cues for a actor who wears a mask. The actor sings, speaks, and dances to the rhythm and chant of the five musicians in the background. There seems to be five actors also, one main character with a role as a warrior of some sort.

The division between musicians and actors is clear due to clothing attire. The musicians are playing mainly rhythmic percussive instruments, although there is one outcast that happens to play a reed like instrument. Most likely this instrument is a sho, hichiriki, or ryuteki, but due to quality it is hard to pin down which one it is.

The audience takes a small role during the performance, like a many Western plays.