Piano question

[melharding]

What is the name of a piece of piano music which was compsed in the 20th century where two pianos were used and were tuned a semitone apart?And who was the composer?

[heffalump]

Charles Ives wrote three pieces for two pianos tuned a quarter-tone apart - titled (rather unimagintively) 3 Quarter-Tone Piano Pieces (1923-4) - is this what you're looking for?

[melharding]

that is perfect thanks so much!