not sure if this falls under the definition of music, but it's certainly is electronic.
Dick Raaymakers (also Raaijmakers; 1 September 1930 – 4 September 2013) was a Dutch composer, theater maker and theorist. He was known as a pioneer in the field of electronic music and tape music. In addition, he realized numerous music theater pieces, art installations, and has published many theoretical essays.
Canon-5, super ‘dis-moi …’ (1967)