Sphärophon

Sphärophon *electrophonic instr. invented by Jörg Mager in 1921, a monophonic instr. of the electrophonic type, originally designed for quarter-tone music. With the addition of a keyboard in 1928, the name was changed to Klaviatur-Sphärophon. Another variety was known as Kurbel-Sphärophon.