Merzbow is harsh noise indeed! It's Masami Akita's brainchild, he's been at it since the early 1980s, and there's been no stopping ever since!! He has about 300 releases under his belt, including the infamous Merzbox, a 53-CD box set featuring a LOT of extras like 2 t-shirts, posters, official biography... an acquired taste indeed.
There's a whole Japanese scene that exists primarily because of Merzbow, artists like Masonna or the Gerogerigegege... but no one touches Merzbow.