Rocker Chris Cornell is calling on former Soundgarden bandmate KIM THAYIL to follow through with his promise to release the band's rarest material - because he'd love to hear it again. The former Audioslave frontman insists a Soundgarden reunion is unlikely, but he's all for Thayil's plans to compile the grunge group's unreleased gems for an upcoming album. Cornell says, "I've left that in Kim's world, because Kim had always talked about wanting to be in charge of doing, like, a box set or a B-sides album. "That was something that he had mentioned years ago, and I'm sure at some point he will want to do it. "I don't know how much actual unreleased stuff is out there, but there's definitely some Soundgarden rarities stuff that the average fan has not heard and it would be nice to put out." Soundgarden split in 1997.