For the penultimate volume of his edition of Carl Philipp Emanuel Bach's complete solo keyboard works, a project he launched nearly thirty years ago, Miklos Spanyi turns to the organ.Bach is remembered as a master of the clavichord and fortepiano - but the organ? In 1755, he composed four sonatas for Princess Anna Amalia's new palace organ in Berlin, works intimate enough for a royal amateur yet rich with the expressive depth that defined his art. A contemporary marvelled that Bach could unite the deepest secrets of art with everything that taste treasures at the organ. These sonatas, together with a mysterious Adagio in D minor whose layered revisions offer a rare window into Bach's compositional workshop, reveal a lesser-known but compelling side of his output. Spanyi performs on a Saxon-style organ in the Calvary Church in Szombathely, Hungary, built in 1986 by the Eule factory and modelled on the Silbermann tradition directly connected to the Bach family. Tuned to 415 Hz in period temperament, it brings an authenticity of colour and character perfectly suited to this music. Few in number, these organ works are no mere footnotes - they are essential C.P.E. Bach.