The last time Vivian Campbell heard Def Leppard's new album, it was shaping up to be "on the heavier side," but things may have changed since then.

Campbell explained the situation during a recent interview with the Ontario classic rock station Free 98.1 FM (which you can listen to below), reminding listeners that while he was involved in the early sessions for the record, his ongoing health issues have prevented him from keeping an active hand -- and although they had a blast playing live in the studio during the initial tracking dates for the project, "the way Def Leppard records work, the last guy in the studio gets to have the final word. So who knows?"

Whatever it ends up sounding like, fans should be able to hear it for themselves soon; Campbell says most of the record is finished, with vocals and a handful of overdubs still needing to be tracked. Saying singer Joe Elliott has been in the driver's seat during this stage, Campbell explained, "We cut a bunch of tracks and we basically left it all in Joe's hands. We said, 'Joe, go and write some lyrics and sing on this.' So the weight is on his shoulders to get this done."

Speculating that the album will be out by mid-2015 with a single shipped to radio before they head back out on tour, Campbell laughed, "I have no idea what the final thing's gonna be. All I can tell you is my involvement was with the first part of the record, and it was a hard rock record at that stage -- so if it comes out being wussy, I'm not accepting blame, you know what I mean? I'm throwing my hands in the air."

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