I was following the Usenet newsgroup rec.music.industrial from 1991. Around 94-95 discussions about japnoise became more frequent, with extremely informed participants such as Mason Jones (Charnel House), Brian Duguid (EST magazine), Roy K. Felps (Körperswache, Monotremata label), Ares Solis (Eskathos magazine), Dan Kletter (Flying Esophagus label), and many more I can't recall now. Some of which I kept in touch with for years. Then as was mentioned the alt.noise newsgroup existed in parallell but it never became as useful as r.m.i. in my opinion, partly because many Usenet admins wouldn't have their servers carrying the cesspool of alt.* groups
There around the mid-90's the mailing lists started to pop up too... cold meat, world serpent, malignant, etc.