*** CHARLIE HADEN & PAT METHENY, “Beyond the Missouri Sky (Short Stories),” Verve; ** 1/2 PAT METHENY GROUP, “Quartet,” Geffen

If it weren’t for the fact that Charlie Haden continually pops up in all sorts of performances, it would be easy to assume that he spends most of his time in recording studios. With the much younger Christian McBride, he is one of the two busiest and most visible jazz bassists of the ‘90s.

What makes Haden a particularly fascinating artist, however, is neither his productivity nor his frequent presence. It is his musical curiosity. He seems to revel in placing himself in unusual creative surroundings. At any given time, he might be performing with his Quartet West ensemble, he might--as he did recently--be at a club performing improvisational material with Lee Konitz, or he might be recording spirituals with pianist Hank Jones.

This time out, Haden performs in a duo setting with guitarist Pat Metheny--yet another challenging environment. Although Metheny does a bit of overdubbing in spots, and there is some minimal usage of synthesizer textures, this is largely a two-man operation, with the focus of the activity placed upon the elegant, understated interaction between these two talented players.

The mood is pensive, laid-back, even a bit sentimental in spots. But the results are lovely. Typically, the material ranges widely, from originals by both musicians to such offbeat items as Henry Mancini’s lovely ballad “Two for the Road,” Jim Webb’s “The Moon’s a Harsh Mistress” and two Ennio Morricone themes from the film “Cinema Paradiso.” On his own “Tears of Rain,” Metheny introduces the evocative sound of his newly acquired guitar-sitar.

Metheny takes most of the leads, performing with a more melodic bent than usual, articulating his lines with the declamatory emotion of a jazz singer. Haden assumes a more elusive role, supporting Metheny with a rhythmic flow that implies the meter more often than it states it, occasionally surfacing (as in his “Waltz for Ruth”) to gently spell out a melody. But it is obvious throughout that Haden and Metheny, both Midwesterners, share a collective musical view, a capacity to enrich their jazz performances with layers of subtle interior emotions.

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Metheny’s “Quartet” album, which has been near the top of the Billboard jazz charts since its release late last year, is a similar attempt to function in a moody, acoustic musical universe. The idea, according to Metheny, was to “play music that was assembled with little rehearsal or improvised entirely.”

Sometimes the strategy works, sometimes it doesn’t. A few of the tracks--”Badland” is typical--have the atmospheric but essentially detached feeling of film background music. Some--”Take Me There,” for example--have the propulsive momentum of the quartet’s essential repertoire. Other tracks--”As I Am” is one--occasionally approach (but don’t quite reach) the floating lyricism of the Metheny-Haden combination.

But the biggest difference between the two albums is in the material. As good as Metheny, Lyle Mays, Steve Rodby and Paul Wertico are, their spontaneous improvisations simply never quite achieve the compelling musical continuity of more thoughtfully crafted pieces.--Don Heckman

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