These 63 tracks, recorded between January 1937 and February 1939, are the key to Count Basie’s legacy. The band had moved to New York from Kansas City, bringing with it a jumping, hard-swinging style of big band blues driven by the rhythm section of guitarist Freddie Green, bassist Walter Page and drummer Jo Jones, plus the leader’s minimalist but perfectly timed comping and all-too-brief solos. The primary tenor sax soloist is Lester Young, who made his name with Basie, and trumpeters Buck Clayton and Harry “Sweets” Edison are also key to the group’s sound. Duke Ellington’s swing was refined and sophisticated; Basie’s was pure energy music, and all his masterpieces are here.