Almost without exception jazz musicians establish a "voice" and then remain fixed in a particular school. This is not to say that they no longer create within the boundaries of that style. But it is to say that very few venture beyond those boundaries, and fewer still with artistic success.

As a member of the Woody Herman "Four Brothers" sax section and later as a seminal player of the "cool" school of the '50s, Stan Getz's impact was principally contained in his ability to project his individuality within a musical phrase.

Last night at Blues Alley the basic Getzian sonorities were ther, as he demonstrated his lyrical skills on "Willo Weep for Me" and his attack on Wayne Shorter's "Lester Left Town."

The remaining five numbers of the first set were originals by members of his rhythm section and it is Getz's choice of these four young musicians that one can see the new and challenging direction that he is taking. Guitarist Chuck Loeb contributed two compositions, "Hotcha" and a fusion-like untitle piece which can only be described as a spellbinder. His brilliance as a solist was present on these as on Andy Laverne's "Pretty City," which displayed the composer's thorough understanding of contemporary jazz piano.

The impeccable musicianship of bassist John Burr and drummer Victor Jones is further proof of the high standards Stan Getz has set for his venture into a new space.

The Stan Getz Quintet remains at Blues Alley through Sunday.