First death metal vocals?
And no The Who's Boris the Spider does not count but yeah close. Its a little too Inspector Gadget Dr Claw
This album is so mind blowing to me I think there's actually a few instances but I'm mostly talking about towards the end of Annalisa
I also think Yoko Ono almost a decade early might qualify as the first death metal vocals and what a coincidence the last song on this album has a moment or two of striking similarity to her.