A prelude by Sergei Rachmaninoff (D major, op. 23 no. 4) played by Lazar Berman.
Jean Ritchie, one of the greatest American folk singers.
Some of this is very much related in style to the Rumanian singing that was kind of famous here in the 80s-90s. At least we certainly noticed it when I was a music student in Tromsø.