A 1970 Buenos Aires LP of Alban Berg’s Chamber Concerto leads back to a 1954 Vienna recording session, a Hannover-born conductor Alma Mahler had trusted, and a New Year’s Eve ritual in a Greenwich Village townhouse where two record producers poured molten lead into cold water and read the shapes.

I intended to make a biography. The working title was simply George Bristow, and the plan was straightforward: rescue a forgotten American composer from the obscurity into which history had carelessly dropped him, and let audiences discover what they had been missing.