All this jazz

Morrison's fusion of his Irish heritage with rock, country blues, and soul has always included a healthy dose of jazz. At his best, he blurs the lines separating his influences, never entirely inhabiting any of them. When he covers an Irish folk tune or a Ray Charles hit, he may not sing it authentically, but there's never any doubt he knows exactly what the song is about. When it comes to jazz, he doesn't swing like Joe Williams (for that matter, Joe Williams probably couldn't get "Astral Weeks" right either), but that's not the point. His achievement is to find an approach to his sources that doesn't ape them.

Morrison relaxes and enjoys himself on his "first jazz album." It has the same unpretentious hanging-out quality that made Irish Heartbeat (Mercury), his release with the Chieftains, so enjoyable. Recorded at Ronnie Scott's, London's answer to the Village Vanguard, the disc features an octet that includes longtime collaborators Georgie Fame on Hammond B3 and JB Horns saxophonist Pee Wee Ellis. The material runs toward the kind of crossover stuff you could hear on the radio in the '50s and early '60s by black musicians like Ray Charles and Cannonball Adderley -- and by white pop singers like Sinatra. Morrison also reworks four originals, including breezy, unaffected versions of "I Will Be There" and "All Saints' Day," and a "Moondance" that is less perfunctory than usual.

But it's on the covers that you really appreciate his artistry. On Charles's blues waltz "Early in the Morning" and Adderley's soul-jazz classic "Sack o' Woe," he slurs the lyrics so they glide hornlike over the band. The words may not be clear, but his mangled articulation is unquestionably the sound of a man wrestling with the blues. For all his idiosyncratic mannerisms, on Charlie Parker's "The New Symphony Sid" (with Fame) and on "Centerpiece" (with Fame and special guest vocalist Annie Ross), Morrison enunciates complex ensemble vocalese with unexpected ease and clarity.

Not that he always makes the right choices. On the title track, he rushes the first two choruses, mis-emphasizing words. But he seems to grow into the song; by the third verse, he's completely given himself over to it. The final "How long has this been going on?" lies exactly in the groove, a perfect expression of wonder and grace. In spite of its awkward start, maybe even because of it, this is one of his most enraptured performances on disc.

Jack Bruce came up through the same '60s British blues-rock scene that also nurtured Morrison. In many ways Bruce helped define it, working early with Alexis Korner and the Graham Bond Organization, singing and playing bass in Cream with Eric Clapton and Ginger Baker. After Cream split up, Bruce turned to jazz-rock fusion, which was just then coming into its own. He made two very credible jazz-rock albums as a leader, Things We Like with John McLaughlin and the even better Harmony Row (both on Atco). He also joined Tony Williams's Lifetime for an album and was part of several Carla Bley/Mike Mantler productions. But only in 1982, when producer Kip Hanrahan cast him as the male voice on his albums, did he begin to realize his potential as a vocalist.

Alone at the piano with only Bernie Worrell accompanying him on B3, Bruce turns in a stunning vocal performance on Moonjack. On "The Food," which he wrote with Hanrahan, he mines deep veins of sadness and rage, at the same time exposing deep wounds. On this tune and "Time Repairs," his controlled vibrato wrings every expressive possibility from words and music. Throughout the album, he moves effortlessly through his range. On Hanrahan's "David's Harp" and on "Laughing on Music Street" (one of the album's several collaborations with longtime writing partner Pete Brown), his soft Scots tenor is dark and matter-of-fact, whereas his falsetto seems to transcend pain, soaring to aching heights. If Bruce has any failing as a singer, it's a tendency toward the operatic that is sometimes at odds with his earthier side. All in all, though, he's never sounded better on disc.

Jazz elements are less obvious on Moonjack than on the Morrison disc, though there are patent references to jazz's roots in gospel music and the blues. Jazz is also felt in Bruce's bumpy stride and more subtly in the elaborate structure and harmonic sophistication of the songs. But it's in the most elusive aspects of this music that Bruce and Morrison owe their greatest debt to jazz: an adventurous spirit and a sense of freedom.