Roger Glover is one of those credit lines I trust on sight: a Welsh bassist, producer, and songwriter who helped define the heavyweight “engine room” of classic hard rock. I mainly tag him to two eras that just refuse to die: Deep Purple (1969–1973, 1984–present), where his bass and writing instincts locked in with that Mark II bite, and Rainbow (1979–1984), where he wasn’t just playing low-end—he was also steering the sound as lyricist and producer. He came up through Episode Six, then spent the 1970s stacking production work and side projects like it was a second career (because, yeah, it basically was), but those Purple and Rainbow years are the real “mythology in the liner notes” stuff.