Pro Musica Hebraica welcomes back the Apollo Ensemble for an evening of rare Jewish classical music from Amsterdam’s Ets-Chaim Library. Since their highly praised American debut in 2009, the musicians have been in great demand internationally for their performances of Jewish baroque music on period instruments. As required, the ensemble can expand from the core chamber group to a full orchestra. Violinist David Rabinovich, a member of both TAE and the Amsterdam Baroque Orchestra, talked about the discovery of several works in the library and their reconstruction by Ton Koopman, founder of the ABO.