This seven-CD limited-edition box set from Mosaic can be evaluated two different ways. Usually Mosaic concentrates on reissuing timeless music that is rare, but that really is not true with the great majority of these 165 selections, which are readily available elsewhere. The Bix Beiderbecke selections are on Sunbeam CDs, the Frankie Trumbauer sessions have been put out by Old Masters, and Jack Teagarden's dates have been reissued by Classics. There are a few scarce alternate takes (only one not out before), two numbers from 1924 by Lanin's Arkansaw Travelers (included because of Trumbauer's solos), and a couple sessions nominally under the leadership of altoist Gil Rodin (notable for Teagarden's playing), but otherwise the music is easy to acquire elsewhere. However, that reservation aside, there are so many classics included in this deluxe set that this box deserves the highest rating anyway. Other than the Lanin numbers, the box really begins in 1927 with the Trumbauer session that resulted in "Singin' the Blues," which has the most famous recorded solos by Bix and Tram. Beiderbecke was at the peak of his powers in 1927. His cornet playing was simply beautiful and he had a very original tone, full of inner heat and thoughtful beauty. His playing on the Trumbauer dates of 1927-1928 and his own Dixieland-ish sets (Bix & His Gang) were among the top moments of 1920s jazz. These include such classics as "Clarinet Marmalade," "I'm Coming Virginia," his piano solo "In a Mist," and "Royal Garden Blues." Even his decline in 1929 (which includes occasional clams) is worth hearing. While Beiderbecke disappears completely near the beginning of the fourth disc (replaced by Andy Secrest), Trumbauer is heard on most of the selections, leading dates through 1936. A master of the soon-to-be-extinct C-melody sax, Trumbauer was one of jazz's first great saxophone soloists and an influence on both Benny Carter and Lester Young. His sessions gradually evolve from classic jazz to swing, and even with a few novelty numbers, the post-Beiderbecke dates are mostly of strong interest. Teagarden, whose arrival in New York in 1928 found him immediately being recognized as jazz's top trombone soloist in addition to being considered a fine blues-oriented vocalist, is heard with Rodin and leading dates of his own during 1930-1934, before he became a sideman in Trumbauer's later sessions (during a period when they were both regularly employed with the Paul Whiteman Orchestra). In addition to the principals, along the way such major performers as clarinetist Jimmy Dorsey, guitarist Eddie Lang, violinist Joe Venuti, bass saxophonist Adrian Rollini, clarinetist Pee Wee Russell, Bing Crosby (on his most jazz-oriented sides), Johnny Mercer, tenors Eddie Miller and Bud Freeman, pianist Fats Waller, Benny Goodman, and trumpeter Charlie Teagarden (Jack's younger brother) make significant contributions to the music. Listeners who do not already own this music and want a large slice of late-'20s/early-'30s jazz history should acquire this valuable box while they can.