Here’s a daunting realization: The Black Keys have been releasing albums for almost 20 years. They’ve been a couple different bands in that time. For years, they were prolific purveyors of a scuzzy, heavy garage indie-blues, each album offering a slight variation or refinement on a pretty immediately established theme. But 10 years ago, there was a pivot point in their career. They released Brothers, and everything began to change.