Crosby was such an icon of middle-of-the-road entertainment that it's difficult to remember he started as a rhythm singer who, beginning in the late-1920s, basically brought the innovations of Louis Armstrong to the mainstream white audience. Of course, when he had hits with the softer ballads characteristic of the Depression years, jazz buffs began to ignore him, though generations of jazz musicians learned to play the hundreds of songs he turned into standards. These 160 items, the huge majority previously unissued, show that his mid-50s repertoire covered everything from the 1915 ‘Chinatown’ to then-new items such as ‘Young And Foolish’ (later covered by Bill Evans). The 15 sessions involved were all intended to be split up for Crosby's weekly radio slots, and feature him at a peak of musicality and relaxation less evident on formal recording dates. The accompaniments are highly professional and mostly unambitious, while the one long set with a Dixieland front-line is a disappointment if you're looking for improvisation. But the singing is something else.