Recording these Mozart Sonatas at the Germaniches Nationalmuseum in Nuremberg on their his-toric fortepiano built by Johann Andreas Stein in 1788, one of the earliest playable pianos still in existence, was a genuine adventure. Stein is generally considered to be the earliest piano maker to create truly viable instruments for concert performance. In 1777 Mozart visited Stein’s workshop in Augsburg in order to observe his manufacturing techniques and of course try out his pianos. He reported back to his father in great detail about the virtues of Stein’s pianos and on the care that the master builder took in his quest to get the mechanics just right. For me it was an exhilarating experience to spend a week and a half exploring and getting to know one of Stein’s pianos just as Mozart had done two and a quarter centuries earlier. It was a voy-age of discovery that I felt we shared. But I quickly came to the realization that, like Mozart’s own early sonatas, each of Stein’s instruments was an experiment, a work in progress. Like all piano mak-ers of the period he relied on the comments and demands of performers for suggestions on how to improve and modify his designs.