Heinz Bohlen
Heinz P. Bohlen was a microwave electronics and communications engineer.
He designed and described numerous non-octave musical scales, many based on combination tones, including the Bohlen–Pierce scale in 1972, the A12 scale, and the 833 cents scale.
Bohlen began to question and investigate tunings in the early 1970s when a friend and graduate student at the Hamburg Hochschule für Musik und Theater asked him to begin recording concerts at the school. Bohlen asked students why all their music used twelve-tone equal temperament, including the octave, and, dissatisfied with the answers, began to investigate alternate tunings.
