Rudhyar was better known as a New Age philosopher, but he wrote a fairly large amount of advanced, atmospheric music for the piano which is almost completely unknown. It's not unlike Abel Decaux's Clairs de Lune, which was also largely unknown until David Dubal brought it to attention.

There is only one recording on Youtube, and it is this one by Masselos:

Fascinating and beautiful! Thanks for sharing.

-Daniel