Following World War II, he returned to the concert stage. His technique was described as "Lisztian" and his repertoire universal, although later in his career his playing of Bartók was much in demand. Initially he recorded numerous piano works by Bach, Beethoven, Brahms, Chopin, Liszt, Rachmaninov, Schumann and others for Columbia Masterworks. Then with Vox, he recorded the complete works for solo piano of Zoltán Kodály and of Sergei Prokofiev; and the complete piano works of Béla Bartók; for the latter he won the Grand Prix du Disque of the Charles Cros Academy in 1965.
Family
In 1950 he married Christa, née Satzger de Bálványos, the divorced wife of Archduke Karl Pius of Austria. They had one son, Michael, and were divorced.
He wrote a book "On Piano Playing: Motion, Sound, Expression", published by Schirmer Books, which is one of the most rational and clear accounts of piano technique. "Today more than ever, audiences mistake the excessively tense muscular activities of the performer for an intense musical experience, and all too often we see the public impressed and awed by convulsive distortions and spastic gyrations." Writing in The Guardian newspaper, Leo Black commented "musical performance desperately needs the sense of rightness, completeness and economy that pervaded his playing and thinking". "On Piano Playing" details approaches to many problems that pianists face. Sándor emphasized the use of gravity, an endless source of energy, during playing. Ideas on memorizing are also addressed. Importantly,"On Piano Playing" corrects these common misconceptions: pianists only play with their fingers and only a few have the physical ability to play the piano. A manuscript of a book on his mentor Béla Bartók and his music remains unpublished. He produced several piano transcriptions, including a fantastically difficult arrangement of The Sorcerer's Apprentice by Dukas, and the first two movements of Bartók's Sonata for Solo Violin. He also edited and published Bartók's own unpublished piano arrangement of the Concerto for Orchestra, at the request of the composer's son in 1985. It was published in 2001, and has been recorded by Sándor. Sándor wrote in his introduction to the edition: "It was agreed that the primary goal would not be to make the piano score easier to play, but to make it playable at all. Furthermore, since Bartók's piano score contains only the first ending of the last movement, my role was to provide a reading for the second ending. Bartók wrote the second ending to avoid the rather abrupt conclusion of this grandiose work, and this is now accepted as the standard version of the last movement." He also edited the works for solo piano of Sergei Prokofiev.
