From Mr Wagener himself:
On what is left of my stuff on Ozzmosis and various reissues I used a late 70s Neumann U87, a John Hardy M1 mic pre and a Summit Tube compressor. Reverb was the 480L on a large hall setting.
Ozzy doubles each line he sings right away, he sings it until we like it, then doubles it once, that is his sound, no chorus or effects used (I only use hardware plug-ins at WireWorld )
For "Live And Loud" I used 6 different harmonizer channels (2x 910, 2x AMS, 2x 949) on his vocals to get close to his sound, but I feel it never really got there.