A very high tone of metallic percussion is main instrument for this piece. 
In case of volume, Taiko is very loud and conspicuous. However brilliant
tone of metallic percussion has very important role for percussion
performance. It will lead a rhythm and provide a sign for others. In this
piece, a Kane (kind of bell) and a Chappa (small cymbal which is brought
from China) are main instruments and Taiko is sub instruments as 
supporter. 
Gaku means that everybody (both listeners and players), let’s have a fun!
Nothing more special meaning than this.