Wikipedia
is a portmanteau of the words "Japanese" and "noise": a term applied to the diverse, prolific, and influential noise music scene of Japan. Primarily popular and active in the 1980s and 1990s but still alive today, the Japanoise scene is defined by a remarkable sense of musical freedom. Some of the most popular groups range from the high-energy free improv stylings of Hijokaidan, the frenzied hardcore-punk-influenced noise of Masonna, the punk demolition of Hanatarash and its subsequent psychedelic Boredoms evolutions, to the tabletop electronics of Incapacitants and Merzbow. Aside from artists often releasing tapes and records in extremely limited quantities, countless side-projects, and collaborations exist within and outside the scene, making the pursuit of Japanoise media an intimidating quest for collectors. Japanoise, and particularly harsh noise, as opposed to some other post-industrial related styles, is often much less aggressively "serious" image-based, being focused more on the sole act of "jamming" as hard, loud or ridiculously as possible.
Nick Cain of The Wire identifies the "primacy of Japanese Noise artists like Merzbow, Hijokaidan and Incapacitants" as one of the major developments in noise music since 1990.
Certain Japanese noise artists themselves feel uncomfortable being categorized under the umbrella of "Japanese noise", arguing that use of the term is a way of ignoring the differences between musicians who don't necessarily follow the same approach or even know each other at all.