Around 1902, German acoustician Dr. Edwin Welte developed a recording system by making greater use of electrical sensors, carbon contacts, and mercury conductors. The Welte Vorsetzer captured everything the pianist did to the instrument during a performance, and classical musicians flocked to have their performances recorded by the device. Listen to actual performances recorded on piano rolls. Hear selections performed by Debussy, Chopin and other classical composers.
In a traditional player piano, the paper roll mechanism is built into the piano. The Vorsetzer (literally "sitter in front") was a device which was rolled up to the keyboard of a grand piano. The device had a felt covered wooden arm or finger for each note on the piano, and the music played was considered a faithful reproduction of the original performance. This is the basis for the syndicated program Keyboard Immortals radio series on Classical Radio dot Network Sundays at 1200 GMT.