More than any other medium, cassette tape was to dominate the recorded music and data market for nearly the whole second half of the 20th Century. From groovy reel to reel tapes, compact cassettes with their colourful boxes and big hi-tech computer data reels, all were based off a clever idea that simply required a thin bit of plastic coated with a metal oxide that could be magnetised and read back at will. Tape’s low cost of manufacture, relative strength and ease of editing and rerecording made it a phenomenal success. But while most people know of tape’s dramatic effect on the post WW2 world, far fewer people know about its pre-war creation. This is because its birth took place during 1930s Nazi Germany and involved some of the largest German manufacturing firms of the time.
Although the original invention hit the global press in 1935, as tension and war loomed ever closer tape’s very existence sank into the limelight to become a nationally guarded tool until the end of the war in 1945. When the conquering Allies did finally see the latest tape players they of course realised the market potential for such an invention and unfairly stripped Germany of its existing patents to be able to produce it freely back at home. And since no-one wanted any connection with the newly defeated Nazi regime, the pre-war history of magnetic tape recording was usually omitted from most of the narratives thereafter.
Poulson’s Telegraphone c.1906
The formulation of an idea:
Back in 1898 a Danish engineer called Valdemar Poulson had invented a way to electrically record speech onto a length of wire using a magnetic principle. His machine was called the Telegraphone and was hailed as the future of office dictation. However, while wire was certainly a stronger material than the wax cylinders it was competing against, the quality of wire recorders were never that great. Ultimately the Telegraphone failed in the early 20th Century to obtain the commercial success it needed but Poulson’s idea at least did serve to inspire other inventors. One of those was a German-Austrian engineer called Fritz Pfleumer (1881-1945).
During the 1920s Pfleumer began working on modifying Poulson’s magnetic principle to work on paper tape instead of wire. During his career he had already successfully developed a process for layering metal strips onto cigarette paper, and realising he may be able to use this approach tried coating 16mm thick paper with a layer of powdered bronze. Since bronze proved neither cheap nor that effective, in 1927 he modified his design further by replacing the bronze with a layer of powdered iron oxide which was glued on to the paper using lacquer. This iron lacquered paper was prone to breaking but worked as a medium to record sound none the less. Therefore in 1928 Pfleumer patented his new invention calling it ‘sound paper’.
Although ‘sound paper’ clearly had its faults, its wide commercial potential was recognised by German industry. This new recording paper was as easy to edit as movie reels making it a possible contender for recording the sound on the new ‘talkie’ movies of the day, yet was superior to celluloid reels because it could also be re-recorded. In December 1932 Pfleumer finally granted the German electrical giant AEG the right to use his invention so they could create the world’s first practical tape player. As AEG realised their skill lay in the mechanics of the machine itself, it brought another company on board (AG Farben- later to be rebranded as BASF) to help further develop the tape. Farben had ample experience working with the newly emerging plastics industry, so when Pfleumer suggested his fragile paper base could be replaced with cellulose acetate instead, they were happy to oblige. The first official trials began in 1933 and AEG’s new machine was to be named the ‘Magnetofon’ or ‘magnetic phonograph’. Because the first model was compact it was sub branded the K1 which was short for ‘Koffer’ (meaning portable) but later cabinet models would also be introduced.
The launch:
When developing a new product it is easy for those involved to try to get the product launched as quickly as possible to prevent competitors from stealing the idea and market, but to the credit of those involved, the official unveiling of magnetic tape was actually postponed by a whole year. Originally AEG had intended for their machine to be launched at the 1934 Berlin Radio Exhibition and 50,000 meters of tape had been produced for demonstration use during the event. However, when AEG’s prototype machine acquired glitches merely two days before the start of the event, it was decided to delay the unveiling.
The launch finally took place in 1935 and rightly caused a stir. The machine was offered for the same price as a comparable gramophone and the tape came out a third cheaper than wire recording. Also by this time AG Farben had refined the tape further and narrowed it to only 6.5mm. They called their tape the ‘type C’ and it was to remain largely unmodified in this form all the way up into the 1960s.
Despite all the initial enthusiasm, by 1940 only 100 machines had been built each year, mostly going to a few businesses as Dictaphones, the radio industry for their stations and the military for use recording those long propaganda speeches. As a useful tool, the war naturally led to an increase in production for tape and tape players of about 500 machines per year. There were also further key improvements in the quality of reproduction, but by this time magnetic tape had become somewhat of a closely guarded tool for the Germans and their allies.
Post War tactics:
Although the world knew about the Magnetofon before WW2 it is fair to say that the early results for recording music was lower than shellac 78s. This perhaps helps explain why the Allied nations didn’t take more notice of it during the war. However when the hostilities were over and military intelligence in both the US and UK did a stock take of German’s commercial resources, they both quickly realised that the Magnetofon had actually been substantially refined during the intervening years to create a vastly superior product than they had known. Indeed AEG and AG Farben had succeeded in creating the first Hi Fidelity and Stereo recordings and it was not long before the Allied nations were copying the technology for their own companies back home.
Sadly for Fritz Pfleumer who invented it all, he died in 1945 just a year or two before his magnetic cassette tape began to truly dominate the world music industry.
Photo attribution: Poulson’s Telegraphone by Internet Archive Book Images ; Magnetophon Images from the 1946 BIOS Report no.951.