The Grundig Stenorette office dictation system used conventional 1/4" tape wound up in a plastic cassette. The tape ended in a loop which was slipped over a peg in the driving spool of the machine. Unlike conventional tape recorders, the tape was driven by being wound onto a captive spool which rotated at constant speed; as the driven spool filled, the tape speed increased. This speed variation, and the non-standard casette spindle fitting, makes Stenorette recordings difficult to play correctly on conventional tape recorders, so an original machine must be used. Poppy Records has a specially-modified Grundig Stenorette machine for playing back these recordings with the best possible sound quality.