Despite the fitness savvy titles, Christian Wolff’s series of Exercises aren’t formulated to inspire the local gym’s spinning class. In this music, like much of the composer’s oeuvre, something seems eerily missing. Melody, rhythm, and harmony sound aloof to one another’s presence, creating a tentative atmosphere of happy accidents. These mishaps usually err on the side of profound rather than tragic. Take Exercise 18, a hodgepodge of passages that has the potential to synchronize into a familiar waltz, but things don’t turn out so obviously. This stuttering passacaglia sounds as if it could have been homebrewed in the tool shed out back. You can attribute this to Wolff’s open design in terms of both instrumentation and interpretation, as well as the adventurous groups of performers which include fellow composers Fredrick Rzewski (piano, percussion), Larry Polansky (electric guitar, percussion), and Chiyoko Szlavnics (soprano saxophone, percussion) joined by new music percussionist extraordinaire Robyn Schulkowsky.