Aburaya's decorations - Drum
The history of drums in Japan is very old, I know that there was a drum in Japan in the Kofun period (the end of the 3 rd to the 6 th century). There was also the theory that there is a nature that the beat of the drum make himself inspire by "synchronizing" to the heartbeat of the human heart.
The using of the drum in battle was effectively utilized according to this theory.