In Allen Cadwallader, Oliver Schwab-Felisch, and William Pastille, eds. International Forum for Schenkerian Research 1. Georg Olms

The slow movement of Bach’s 1735 Concerto nach Italienischem Gusto evokes in sound and texture concertos by Vivaldi and others that he transcribed some two decades earlier; its form and associated voice leading, however, are Bach’s own. The movement is an astonishingly early example of a “type 1 sonata” (sonata “without development”); moreover, this high-Baroque sonata movement in minor exhibits a unique, remarkably balanced voice-leading structure unavailable to Classical composers bound to a top-voice dependent conception of “theme.” The  sonata-formedness of the movement may be traced to Bach’s experimentation with aria form in his early Leipzig years; this finding corroborates Charles Rosen’s conjecture, that the progenitor of “slow-movement sonata form” is the ritornello-impregnated da capo aria.