See stencil duplicator and Gestetner Cyclograph Company. Technicolor Video Services Inc. was the largest DVD duplicator in the world. Earlier versions included the Gestetner stencil duplicator, invented by David Gestetner in 1887. The mimeograph process should not be confused with the spirit duplicator process. In 1986, the RISO Kagaku Corporation introduced the digital duplicator. This product was soon sped up by fifty percent to become the Xerox 3600 Duplicator. The company introduced the Model 0 Flatbed Duplicator in 1887. Finally in the fall of 2013, he purchased a cassette duplicator for the label. Bizarro tried to steal Superman's duplicator ray. Unlike a spirit duplicator master, a hectograph master is not a mirror image. At age 19 he started working at MCA Music Publishing Studio as a tape duplicator. The spirit duplicator was invented in 1923 by Wilhelm Ritzerfeld. The duplicator uses two-ply "spirit masters", also called "master sheets".