Bassist Ron Carter and guitarist Jim Hall have played jazz for a combined total of nearly 50 years, but their collaborations are rare. One would never have guessed this last night at Blues Alley, for their sensitivity and intuitiveness served as a model to all who practice their craft.

Playing bass and guitar--traditionally rhythm instruments in jazz--in a duo setting is enough to deter even the confident; the musicians must be facile at playing the melody line, soloing and providing sympathetic accompaniment. Carter and Hall achieved this with seemingly no effort.

Particularly striking were Thelonious Monk's "Blue Monk" and Carter's "Little Waltz." On the former, Hall ably combined measured single-note runs with distinctive chord progressions that still did not overpower Carter's easy walking bass. The two made effective use of colors to bring out the moody qualities of "Little Waltz," a ballad.

Only an overreliance on standards and predictable arrangements were dissatisfying in a warm and engaging set. Carter and Hall have the security borne from being at the top of their trade; they know when to hold back and when to embellish. A performance such as theirs shows the understated often speaks the loudest.

Carter and Hall will be at Blues Alley through Saturday.