Mixing and matching the pitches of 20th century classical music and jazz isn't new. (Monk did it, and so did James P. Johnson.) But where most jazz artists swing their weird notes in standard time, the pianist Stacken chooses to absorb the compositional pace of, say, Morton Feldman. Some of his bagatelles for improvising trio don't move very fast, but you can feel their cumulative impact. "Bagatelle No. 2" is a good starter: Propulsive and Schoenberg-like, it shows off drummer Jeff Davis' range to fine effect. And bassist Eivind Opsvik continues his ascent on this memorable recording.