(R)evolution of Portable Audio: Things Getting Reel.

This article focuses on the development and impact of magnetic tape recording technology, originating from a secret German invention during World War II. German engineers at AEG and chemical company IG Farben/BASF introduced polyvinyl chloride (PVC) magnetic tape and the Magnetophon recorder, which, combined with the accidental discovery of AC-biasing, significantly improved audio quality. After the war, U.S. army officer Jack Mullin brought this technology to America, where it was commercialized with the support of entertainer Bing Crosby and companies like Ampex. The article also highlights the evolution of tape recorders through transistor technology, their cultural significance in the mid-20th century, Australian contributions such as the Byer models and the invention of the flight-deck voice recorder by Dr. David Warren, and the eventual transition toward more user-friendly tape formats.