This is one of those motherlode, core-curriculum sets. If you want to understand bebop, if you want to grasp the seismic impact alto saxophonist Charlie Parker and his peers and collaborators had in the 1940s, there’s no better starting point than this three-CD set. The various bands heard on these sessions, all recorded between 1945 and 1948, include trumpeters Dizzy Gillespie and a very young Miles Davis; pianists Erroll Garner, Bud Powell, John Lewis, and Duke Jordan; and drummer Max Roach — all of these men would go on to fundamentally reshape jazz for decades. Considered in context, appearing seemingly ex nihilo as it did at the end of the swing era, after several years when bands had been forbidden to record because of World War II, bebop was almost a punk rock-level revolution, prizing instrumental virtuosity and an almost sarcastic irreverence for traditional songs over what had been jazz’s previous mission: to get the crowd dancing. Parker, Gillespie and the rest wanted you to listen. Fortunately, they wrapped their revolutionary improvisational ideas in catchy tunes with hummable melodies and twitchy, addictive rhythms. There’s a reason jazz musicians are still learning — and playing — these songs more than a half-century later. And Parker himself described his style as “trying to play clean and looking for the pretty notes,” and indeed, even at top speed he’s almost always in control and sculpting melodies, not just strings of notes.