Ensemble 415

Switzerland's Ensemble 415 was among the earliest and steadiest period-instrument groups to make a splash during the 1980s with its recordings on Harmonia Mundi. Almost unfathomably, this afternoon's concert—which brings a mix of pieces by Albinoni, Muffat, Vivaldi, Bach and Henricus Albicastro—is the ensemble's New York debut. (We couldn't believe it either.)