In response to critical carping that his ambitious, evocative music somehow didn't swing enough, Charles Mingus returned to the earthiest and earliest sources of black musical expression, namely the blues, gospel, and old-time New Orleans jazz.

The resulting LP, Blues and Roots, isn't quite as wildly eclectic as usual, but it ranks as arguably Mingus' most joyously swinging outing.

Working with simple forms, Mingus boosts the complexity of the music by assembling a nine-piece outfit and arranging multiple lines to be played simultaneously -- somewhat akin to the Dixieland ensembles of old, but with an acutely modern flavor.

Anyone who had heard "Haitian Fight Song" shouldn't have been surprised that such an album was well within Mingus' range, but jazz's self-appointed guardians have long greeted innovation with reactionary distaste.

After Blues and Roots, there could be no question of Mingus' firm grounding in the basics, nor of his deeply felt affinity with them.

Whether the music is explicitly gospel-based -- like the groundbreaking classic "Wednesday Night Prayer Meeting" -- or not, the whole album is performed with a churchy fervor that rips through both the exuberant swingers and the aching, mournful slow blues.

Still, it's the blues that most prominently inform the feeling of the album, aside from the aforementioned "Wednesday Night Prayer Meeting" and the Jelly Roll Morton tribute "My Jelly Roll Soul." The recording session was reportedly very disorganized, but perhaps that actually helped give the performances the proper feel, since they wound up so loose and free-swinging.

With a lineup including John Handy and Jackie McLean on alto, Booker Ervin on tenor, frequent anchor Pepper Adams on baritone, and Jimmy Knepper and Willie Dennis on trombones, among others, Blues and Roots isn't hurting for fiery soloists, and they help make the album perhaps the most soulful in Mingus' discography.