Tape recorders may not be as important as they once were in modern recording studios, yet magnetic recording technology continues to permeate our lives in the form of hard disks, mag stripes on credit cards, etc. The lineage of magnetic recording can be traced to Danish engineer Valdemar Poulsen (1869-1942), who created the Telegraphone magnetic recorder in 1898.
In his U.S. patent (#661,619) Poulsen described the system as an “essential advance in this branch of science, as it provides for receiving and temporarily storing messages and the like by magnetically exciting paramagnetic bodies... such as a steel wire or ribbon which is moved past an electromagnet connected with an electric or magnetic transmitter, such as a telephone." The Telegraphone medium was steel piano wire wrapped in a tight spiral around a small brass cylinder, although Poulsen later developed reel-to-reel recorders using spools of wire.
Poulsen's 1900 Telegraphone recording of Austrian Emperor Franz Joseph is the earliest magnetic recording in existence. Listen to a 10-second clip of this historic recording. (Note: The sound clip loads slowly!)
Click here to read Poulsen's original Telegraphone patent.