You don't play the ANS synthesizer with a keyboard. Instead you etch images onto glass sheets covered in black putty and feed them into a machine that shines light through the etchings, trigging a wide range of tones. Etchings made low on the sheets make low tones. High etchings make high tones. The sound is generated in real-time and the tempo depends on how fast you insert the sheets.
This isn't a new Dorkbot or Maker Faire oddity. It's a nearly forgotten Russian synthesizer designed by Evgeny Murzin in 1938. The synth was named after and dedicated to the Russian experimental composer and occultist Alexander Nikolayevich Scriabin (1872–1915). The name might not mean much to you, but it illuminates a long running connection between electronic music and the occult.
While Pierre Schaeffer is often thought of as the father of the electronic music form known as musique concrète the gentleman above, Halim El-Dabh, actually got there several years before, 1944 to be exact. Born in Egypt in 1921, El-Dabh studied agriculture at Cairo University while playing piano and other traditional instruments as a pastime. One day, the student and a friend borrowed a wire recorder -- a device predating magnetic tape -- from the Middle East Radio Station and hit the streets to capture ambient sounds. El-Dabh recorded a spirit-summoning ritual called a zaar ceremony and ultimately found that he could use the sounds as the raw ingredients for a new composition. In a recent interview with the Electronic Music Foundation, El-Dabh, who is University Professor Emeritus of African Ethnomusicology at Kent State University and continues to compose music, tells the story of his musical career, including this bit about the pioneering 1944 piece listenable above, an excerpt from "The Expression of Zaar":
We had to sneak in (to the ritual) with our heads covered like the women, since men were not allowed in. I recorded the music and brought the recording back to the radio station and experimented with modulating the recorded sounds. I emphasized the harmonics of the sound by removing the fundamental tones and changing the reverberation and echo by recording in a space with movable walls. I did some of this using voltage controlled devices. It was not easy to do. I didn't think of it as electronic music, but just as an experience. I called the piece Ta'abir al-Zaar, (The Expression of Zaar). A short version of it has become known as Wire Recorder Piece. At the time in Egypt, nobody else was working with electronic sounds. I was just ecstatic about sounds.