Lately, it seems that each time you put on a new record by a well-known jazz player, you get either disco or Muzak. Obviously, this isn't an absolute rule, but the number of defectors to a supposedly more salable commodity is large and impressive. Stanley Turrentine, Roy Ayers, Charles Earland, Herbie Mann, Donald Byrd and Les McCann have funked up their sounds; Hubert Laws, Grover Washington Jr. and even Stephan Grapelli have buried their essences under lush arrangements in hopes of a hit.

That makes it all the more refreshing when jazz artists, especially younger ones, produce albums that owe nothing to formula, that rely on strength of composition and performance, that trade some sales for a more sincere statement and let listeners know that undiluted jazz is still available.

Woody Shaw, whose band begins a week's run at Blues Alley Tuesday, is younger than Mick Jagger and grew up in rhythm n'blues-oriented Newark. It would be natural if Shaw used rock riffs or disco in his tunes, but his new album, "Stepping Stones - Live at the Village Vanguard," is swinging improvisation of the highest quality.

Shaw's cornet and flugelhorn are backed by Carter Jefferson (tenor and soprano sax), Onaje Allan Gumbs (piano), Clint Houston (bass) and Victor Lewis (drums): smaller than Shaw's usual ensemble, but suited to his fluid style.

"I'm able to handle any kind of music," he has said. "But I think that when it stops swinging, it's not jazz."

With that in mind, Shaw blows through "Stepping Stone" and "In a Capricornian Way" showing a host of influences. Both compositions are his own, but there are musical references to the be-hop of Dizzy Gillespie, the tone of Clifford Brown, the strength of Freddie Hubbard and the spaciousness of Miles Davis.

And it's not just trumpeters who have left their mark. Shaw learned well from musicians he's worked with through the years - people like Bud Powell, Horace Silver, McCoy Tyner and Art Blakey.

All that experience has given Shaw a feel for rhythm that accentuates, rather than obliterates, the melody. The thrust of "Seventh Avenue" and "It All Comes Back to You" is toward accessible composition, but the tunes are unrestricted. It's obvious that Shaw's home in front of the New York audience and they bring out his best.

"Stepping Stones - Live at the Village Vanguard" is a celebration - for Shaw and for those who want new jazz that remembers where the old jazz came from.

Some new jazz seems unrelated to its heritage but is important nonetheless, redefining the boundaries of contemporary music: "new jazz," "free jazz" or "loft jazz," depending on your reference points. Ornette Coleman and Cecil Taylor are generally held responsible for its birth - Miles Davis also had a hand in it, as did others - but, despite the players' credentials, this type of unstructured playing has never caught on commercially. By now many of the musicians involved in the movement should have become discouraged, but most are committed to forging ahead despite the odds against popular success.

Violinist Leroy Jenkins is one of the committed. He has played with most of the acknowledged "heavies" in the field, among them Anthony Braxton, Don Cherry, Cecil Taylor and the late Albert Ayler. Jenkins' own work is best catalogued by his involvement in the Revolutionary Ensemble and by a solo concert recorded in New York City in early 1977. A ll of Jenkins' work shows a drive toward extension, a constant dissatisfaction with current standards.

On "Solo Concert," released last spring, Jenkins stretches each theme to its limit, turning each one over and examining it from a new angle. His Revolutionary Ensemble playing, with drummer Jerome Cooper and bassist Sirone, is well represented on an album made available last summer after the trio had disbanded. Here the instrumental interplay provides a denser sound but the quest is the same.

At 46, Jenkins is no kid, but his concepts are daring and his music as new as it comes. He will be appearing at d.c. space Friday and Saturday, and his new album, "The Legend of Al Glatson," should now be in the stores. Not all stores will carry it, though, since there's not a big market for his records - there probably isn't a big market of people who know who Leroy Jenkins is .

That's mainly because his music isn't easy: It demands close listening, something few of us are willing to take time for. Still, his art continues to develop and his sets this weekend offer a chance to see a fertile mind in progress. You won't be able to dance to the music - he deals with brain, not boogie - but you might discover something new.