This group, largely driven by the energies of St. Paul Chamber Orchestra players, has become an essential part of the classical music scene. They don't perform frequently, but that only makes their work feel more necessary. Steve Copes, Ruggero Allifranchini and Maiya Papach from the SPCO and Tony Ross of the Minnesota Orchestra form the group's core. Their virtuosity and eclectic tastes, up close in venues featuring superior acoustics, make for memorable evenings. 651-292-3267, schubert.org/accordo/