Kurt Cobain recorded backing vocals on some of Hole's 'Live Through This' album - these recordings were pushed pretty far down in the mix to the point of being almost inaudible. A bootleg alternate mix of one of the songs 'Asking For It' with his prominent vocal take was released on Outcesticide V and was rumoured to have been scheduled for a full release but cancelled after his death. Using AI and other tools I manage to peel back the layers in 'Asking For It' and reveal Kurt Cobain's buried backing vocal. I also reconstructed in full the cancelled alternate mix with the restored vocal take which you can hear here:
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