NEW YORK — Stefan Kudelski — inventor of the first professional-quality portable tape recorder, which revolutionized Hollywood moviemaking and vastly expanded the reach of documentarians, independent filmmakers, and eavesdroppers on both sides in the Cold War — died Jan. 26 in Switzerland. He was 83.
His death was announced by the Kudelski Group, the Swiss electronics engineering firm he founded in 1951.
Mr. Kudelski, a native of Poland, was an engineering student at a Swiss university in 1951 when he patented his first portable recording device, the Nagra I, a reel-to-reel tape recorder, about the size of a shoe box and weighing 11 pounds, that produced sound as good as that of most studio recorders, which were phonebooth-size.
The bigger breakthrough came seven years later, when Mr. Kudelski introduced a high-quality tape recorder that could synchronize sound with the frames on a reel of film. His 1958 recorder, the Nagra III, freed a generation of filmmakers from the conventions and high cost of studio production.
Along with the newly developed portable 16-millimeter camera, the Nagra recorder became an essential tool for the on-location, often improvisational techniques of such New Wave directors as François Truffaut and Jean-Luc Godard, and US documentarians as D.A. Pennebaker, who used the Nagra to record the 1965 Bob Dylan tour featured in his classic film ‘‘Don’t Look Back.’’
In various interviews, Pennebaker, Godard, and Truffaut all credited Mr. Kudelski with helping to make possible the informality and journalistic realism of their work.
Mr. Kudelski received Academy Awards for his technical contributions to filmmaking in 1965, 1977, 1978, and 1990 and Emmy Awards in 1984 and 1986.
In the 1960s, Mr. Kudelski’s firm also began making miniature recorders for what its online catalog calls ‘‘surveillance and security’’ work. The first of these pocket-size machines was the SN Serie Noire, which the company’s website boasts was ‘‘originally ordered by President J.F. Kennedy for the American secret services.’’
The collection of bugging devices on display at the International Spy Museum in Washington, a privately financed archive run by former CIA employees, includes a Nagra recorder obtained in the 1980s from Stasi, the East German internal security agency.
The Nagra’s value to customers like those was generally classified. But it received acclaim by consensus from professionals in the radio, television, and film industries.
By the early 1960s, Nagras were the standard recording equipment in all three industries.
They remained dominant until the advent of digital audio recorders in the 1990s.