Since 1991, a complete edition of all recordings in which Karlheinz Stockhausen has personally participated is being released on compact discs. Each CD in this series is identified by Stockhausen's signature followed by an encircled number. The numbers indicate the general historical order of the works. Stockhausen realised the electronic music and participated in these recordings as conductor, performer, sound projectionist, and musical director. He personally mixed down the recordings, mastered them for CDs, wrote the texts and drew the covers.
When Cindy Castillo and Frédéric d'Ursel told me about their project involving the six Sonatas for violin and keyboard by J.-S. Bach and invited me to write pieces for violin and organ to frame two of them, I immediately and intensely felt the challenge. The juxtaposition of styles that would inevitably result implied an equation that was not easy to solve: the music to be created had to be in connection, in dialogue with that of this "Master" - one of the most famous in the entire History of Western Music! In any case, it seemed to me that the project had to aim at a proposal for an overall form whose elements would be brought together in a coherent architecture that would be perceptible to the listener.