Since the late '80s, Seiichi Yamamoto has been active as an amazingly versatile musician, mainly in the Osaka area. Leading and participating in numerous bands and projects, he has demonstrated the great diversity of his musical styles--from rock, folk, and punk to improvisation and noise. Among many others, he formed the avant-rock band Omoide Hatoba in 1987; Rashinban, featuring his vocals, around 1988; the punk band Akabushi in 1993; and the noise duo Ontoko with K.K. Null in 1999. The various bands of which Yamamoto is a member include Boredoms, Novo Tono, Rovo, and Most.

In addition to his activity as a musician, Yamamoto has owned the rock club Bears in Osaka since 1987, and the label Ummo Records since 1997. Ummo Records' releases mainly feature Osaka-area musicians. Yamamoto is without doubt one of the central figures of the Osaka-area underground music scene.