“Ozzy and Sharon were the first ones to believe that I could make them a great rock album,” Watt told Guitar World earlier this year. But the biggest gift of all was the education he got from working with a legend like Ozzy. It’s the bass.’“He pointed out that the bass is the most important thing in a rock song,” Watt continues. "It makes the song heavy because the guitars can poke through if you have them mixed in the right way. The bass is a hard thing to really get cutting, but to also represent the bottom end.