The early ’90s were a transformative period in rock: Not only did you have underground bands like Nirvana and Soundgarden migrating into the mainstream, but already mainstream bands like Guns N’ Roses and Metallica were leaving the ’80s behind and venturing toward something new. It’s easy to tell the story as a changing of the generational guard, but the reality is more like plate tectonics: two forces crashing together and reshaping each other in the process. Metallica may have been closer to our collective image of an arena-rock band—big, brash, made for the masses—but once Nirvana started selling out arenas, who’s to say what an arena-rock band actually was? And if Soundgarden was a major-label band (not to mention the Melvins, Butthole Surfers, The Jesus Lizard, or any of the other wild gambles signed in the wake of Nevermind), what did that say about the underground? So while the tracks here lean on the era’s newer voices, they also capture the older ones in moments of growth and transition—both sides equal players in a moment still resonating in rock culture.