Unique Soviet Synth ANS (BBC documentary)
The ANS was used by Stanislav Kreichi, Alfred Schnittke, Edison Denisov, Sofia Gubaidulina, and other Soviet composers. Edward Artemiev wrote many of his scores of the movies of Andrei Tarkovsky with the help of the ANS. Notably is Artemiev’s score of Tarkovsky’s Solaris in which the ANS was used to abstract, sci-fi effect akin to ambient music.
More info on Wikipedia HERE.