Paul Chambers, one of the great originators in jazz bass playing, had a simple concept to describe the possibilities of his instrument; Bass on top. David Friesen, appearing at the One Step Down through Sunday with guitarist John Stowell, is in the forefront of the new generation of superior jazz bassists that includes Glen Moore, Charlie Haden and Ron Carter on acoustic, and Jaco Pastorius and Stanley Clarke on the electric end.

What elevates Friesen above so many other bassists is a rich total assurance and a rhythmic dexterity that finds him as confortable developing the raga-like structure of the opening "Trilogy" as with the percussive Latin polyrhythms of "Wings of the Wind." Working with other, less challenging structures, he is like a china doll in the bull's pen.

In an unusual turnaround, it's Stowell who functions most frequently as the rhythm keeper on six-and 12-string guitar, mandolin, kalimba and percussion with occasional spots for subdued and intelligent solos. Friesen himself steps off bass for brief stints on piano and shakuhachi. The shimmering strength of the set was drawn from the almost casual interplay of bass and guitar and the beautifully textured cord-like overtones and powerfully assured, often piston-like strokes that Friesen conjured from his 175-year-old instrument.

The music at the One Step Down this weekend may be a bit challenging for its instrumentation; for quality and substance, it's probably not to be matched.