Harmonia Mundi dominates this week’s releases with three rarely performed pieces and all-star casts. Here is a look. Schubert Mass Harmonia Mundi will release Schubert’s Mass in A Flat featuring Anke Vondung, Anna Korondi, Andreas Karasiak, and Kay Stiefermann. The recording features the Orchestre des Champs-Elysse and conductor Herreweghe. Dido and Aeneas Purcell’s “Dido and Aeneas” stars Lynne Dawson, Rosemary {…}