Vocalese is the art of writing lyrics to fit recorded instrumental solos, many of which end up being tongue twisters. Eddie Jefferson was the first important vocalese lyricist in the late '40s -- although a 1929 record (released for the first time in 1996) finds Bee Palmer singing words set to Bix Beiderbecke's solo on "Singing the Blues," Jefferson's words to Gene Ammons' "Red Top," and Charlie Parker's "Parker's Mood." Vocalese reached its highest peak with Lambert, Hendricks & Ross in 1957-62 (a group featuring the genius of vocalese Jon Hendricks, Annie Ross, and Dave Lambert). In later years, Hendricks led the Hendricks Family (which revived many of the Lambert, Hendricks & Ross classics), and Manhattan Transfer sometimes used vocalese. Although it has rarely advanced beyond bop (other than Jefferson's successful transformations of "Freedom Jazz Dance" and "Bitches Brew"), vocalese is still used as an option by today's jazz singers.