Par CHOSTAKOVITCH DIMITRI. Just back from a trip to Leipzig in the early autumn of 1950 where he heard Bach's Well-Tempered Klavier at the Bicentennial Bach Competition played by the Russian pianist Tatiana Nikolaeva, Shostakovich began his own series of 24 Preludes and Fugues, Op. 87, based on Bach's model. He composed them quickly, starting on October 10, 1950, and finishing on February 23, 1951…