Editing Tape recorder (section)

=== American developments ===
Development of magnetic tape recorders in the late 1940s and early 1950s is associated with the [[Brush Development Company]] and its licensee, [[Ampex]].  The equally important development of the magnetic tape medium itself was led by [[Minnesota Mining and Manufacturing]] (3M) corporation.{{citation needed|date=August 2022}}
In 1938, [[Semi Joseph Begun|S.J. Begun]] left Germany and joined the Brush Development Company in the United States, where work continued but attracted little attention until the late 1940s when the company released the very first consumer tape recorder in 1946: the Soundmirror BK 401.<ref name=CLEVE02>{{cite encyclopedia |url=http://ech.case.edu/cgi/article.pl?id=BDC |title=BRUSH DEVELOPMENT CORP |encyclopedia=The Encyclopedia of Cleveland History |date=2002-05-29}}</ref><!--less reliable, but interesting refs: http://esrv.net/brush_bk401.html, http://www.radiomuseum.org/r/brush_bk401.html--> Several other models were quickly released in the following years. Tapes were initially made of paper coated with [[Iron(II,III) oxide|magnetite powder]]. In 1947/48 Minnesota Mining & Manufacturing Company ([[3M]]) replaced the paper backing with [[cellulose acetate]] or [[polyester]], and coated it first with black oxide, and later, to improve signal-to-noise ratio and improve overall superior quality, with red oxide ([[Iron(III) oxide#Gamma phase|gamma ferric oxide]]).<ref>{{cite web |last1=Bruce-Jones |first1=Henry |title=Worldwide gamma ferric oxide shortage delays cassette tape production |url=https://www.factmag.com/2019/10/11/gamma-ferric-oxide-shortage-delays-cassette-tape-production/ |website=www.factmag.com |date=11 October 2019 |publisher=Fact |access-date=8 April 2020}}</ref>{{Citation needed|date=May 2023|reason=Current citation only affirms the use of gamma ferric oxide in manufacture of cassette tapes, and does not reference 3M being involved in the manufacturing process at all.  As of now there is no citation providing evidence for the 3M related content in the preceding sentence.}}

American audio engineer [[John T. Mullin]] and entertainer [[Bing Crosby]] were key players in the commercial development of magnetic tape.  Mullin served in the U.S. Army Signal Corps and was posted to Paris in the final months of WWII.  His unit was assigned to find out everything they could about German radio and electronics, including the investigation of claims that the Germans had been experimenting with high-energy directed radio beams as a means of disabling the electrical systems of aircraft.  Mullin's unit soon amassed a collection of hundreds of low-quality magnetic dictating machines, but it was a chance visit to a studio at [[Bad Nauheim]] near Frankfurt while investigating radio beam rumors, that yielded the real prize.{{citation needed|date=August 2022}}

Mullin was given two suitcase-sized AEG 'Magnetophon' high-fidelity recorders and fifty reels of recording tape.  He had them shipped home<ref name="fenster"/> and over the next two years he worked on the machines constantly, modifying them and improving their performance. His major aim was to interest Hollywood studios in using magnetic tape for movie soundtrack recording.{{citation needed|date=August 2022}}

Mullin gave two public demonstrations of his machines, and they caused a sensation among American audio professionals; many listeners literally could not believe that what they heard was not a live performance.  By luck, Mullin's second demonstration was held at [[MGM Studios]] in Hollywood and in the audience that day was Bing Crosby's technical director, Murdo Mackenzie.  He arranged for Mullin to meet Crosby and in June 1947 he gave Crosby a private demonstration of his magnetic tape recorders.<ref name="fenster"/>

[[Bing Crosby]], a top movie and singing star, was stunned by the amazing sound quality and instantly saw the huge commercial potential of the new machines. Live music was the standard for American radio at the time and the major radio networks didn't permit the use of disc recording in many programs because of their comparatively poor sound quality. Crosby disliked the regimentation of live broadcasts 39 weeks a year,<ref name="fenster"/> preferring the recording studio's relaxed atmosphere and ability to retain the best parts of a performance. He asked NBC to let him pre-record his 1944–45 series on [[transcription disc]]s, but the network refused, so Crosby withdrew from live radio for a year. ABC agreed to let him use transcription discs for the 1946–47 season, but listeners complained about the sound quality.<ref name="fenster">{{cite magazine |author=Fenster, J.M. |url=http://www.americanheritage.com/articles/magazine/it/1994/2/1994_2_52.shtml |title=How Bing Crosby Brought You Audiotape |magazine=Invention & Technology |date=Fall 1994 |archive-url=https://web.archive.org/web/20110404045940/http://www.americanheritage.com/articles/magazine/it/1994/2/1994_2_52.shtml |archive-date=4 April 2011 |url-status=dead}}</ref>

Crosby realised that Mullin's tape recorder technology would enable him to pre-record his radio show with high sound quality and that these tapes could be replayed many times with no appreciable loss of quality. Mullin was asked to tape one show as a test and was subsequently hired as Crosby's chief engineer to pre-record the rest of the series.{{citation needed|date=August 2022}}

Crosby's season premiere on 1 October 1947 was the first magnetic tape broadcast in America.<ref name="fenster"/> He became the first major American music star to use tape to pre-record radio broadcasts, and the first to master commercial recordings on tape. The taped Crosby radio shows were painstakingly edited through tape-splicing to give them a pace and flow that was wholly unprecedented in radio.{{efn|Mullin claims to have been the first to use [[canned laughter]]; at the insistence of Crosby's head writer, Bill Morrow, he inserted a segment of raucous laughter from an earlier show into a joke in a later show that hadn't worked well.}} Soon other radio performers were demanding the ability to pre-record their broadcasts with the high quality of tape, and the recording ban was lifted.<ref name="fenster"/>

Crosby invested $50,000 of his own money into the Californian electronics company [[Ampex]], and the six-man concern (headed by [[Alexander M. Poniatoff]], whose initials became part of the company name) soon became the world leader in the development of tape recording, with its Model 200 tape deck, released in 1948 and developed from Mullin's modified Magnetophons.{{citation needed|date=August 2022}}