Welcoming a new cast of characters to the archival world: Wire recordings

“Wire recording”: 1. Magnetic wire spool; 2. Magnetic wire, itself, spooled

“Wire recorder/player”: 3. Uptake reel; 4. Magnetic wire spool

Dating back as early as 1898, inventor Valdemar Poulson introduced the first magnetic audio recording technology in the magnetic wire and its corresponding recording device, called the telegraphone. The wire itself appears as a thin (4mm) wire usually wrapped around either a 2.75-inch or 3.75-inch diameter reel. Produced primarily from 1939-1955, magnetic wire was made of stainless steel alloy and could reach lengths of up to 7,200 feet depending on the size of the reel. A predecessor of magnetic tape, wire recording occurs when the wire is rapidly pulled across a recording “head” supplied with an electrical signal at the instant of recording. To play back the recorded material, the wire is once again pulled across the “head,” but this time, the head is no long supplied an electrical signal, and the varying magnetic field of the wire “recreates” the original signal, or in other words, the sound of the recording.

 

Maguire, Marsha. “Description of Audio Recordings.” In ARSC Guide to Audio Preservation, edited by Sam Brylawski, Maya Lerman, Robin Pike, and Kathlin Smith, 22. Washington, DC: Library of Congress, 2015.