I love harsh noise, but Merzbow isn't my favourite by a longshot. I tend to favour the originals such as Maurizio Bianchi, Iannis Xennakis, Keiji Haino, and other artists along those lines.
EDIT: Maybe Masonna fits in on the a cappella harsh noise category? He seems to appropriately fit the genre title, but he also does use quite a few effects. That and these all prove me wrong haha. Whoops

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