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Legendary Nagra

If there is anything that can help to understand the fascination of tape recorders, it is the recorders made by Nagra Kudelski and StellaVox. Built for extreme ruggedness and reliability, but at the same time fine like mechanic swiss watches, these machines have set the standards of sound recording systems for motion picture productions.

Wolfgang Bleier, Austria
July 2008, updated in February 2015

"Nagra" origins from the Polish language (nagrac´, nagrany, nagranie) and literally means "record, cut, recorded or recording". Nagra recorders have a reputation for extreme ruggedness and reliability, essentially being a symbol for finest audio tape recorders like the famous Swiss watches are a symbol for fine chronometers. Their cases are highly durable, and every component, from the transport rollers to the gain pots give the feel of excellent engineering. Nagra is a term that refers to the series of professional audio tape recorders produced by NAGRA AUDIO, a company owned by the Kudelski Group SA, based in Cheseaux-sur-Lausanne, Switzerland.

Stefan Kudelskinagra 4.2The founder Stefan Kudelski was an audio engineer with Polish origins, famous for creating the top quality Nagra series of professional audio recorders. He was born in Warsaw on February 27, 1929 in a family with engineering background. In 1939 the family fled the war, moving to Hungary, France and later to Switzerland. He studied at the Swiss Federal Institute of Technology in Lausanne and constructed his first tape recorder there, as a student project. 1951 Stefan Kudelski builds his first Nagra tape recorder. 1957 Kudelski launched the Nagra III, a transistorized tape recorder with electronic speed control, which finally marked his breakthrough. The Nagra III tape recorders became the de-facto standard sound recording systems for motion picture production. He received many awards during his career like the Academy Awards (Oscars™) and Emmy Awards and Gold Medals from L. Warner, AES (Audio Engineering Society), Lyra and Eurotechnica. Nagra tape recorders also prominently appeared in several cinema films.
Stefan Kudelski, the inventor of the first professional-quality portable tape recorder, which revolutionized Hollywood moviemaking and vastly expanded the reach of documentarians, died in January 2013 in Switzerland. He was 83.

The physical appearance of Nagra recorders with their eye-catching "Modulometer", the single transport selector and large reel to reel tape deck are still the stereotypical image most people have of a professional tape recorder. The feature that gave Nagra the edge in quality and film use was Stefan Kudelski's development of the Neo-Pilottone system. With this feature synchronization data could be recorded on the tape in the middle of the audio track, but without crosstalk onto the program recording. Neopilot was the standard synchronization system used in filmmaking until the late 1980s, when timecode became the preferred standard.

Vintage Recorders UK present their collection of fine Nagra tape recorders on YouTube.

Nagra recorders
are identified by their model number, which indicate their technological generation and features:

Nagra I   The very first prototype with clockwork motor and miniature tubes, appearing in 1951. Two of them were sold to Radio Genève.
Nagra II   The first production model, miniature tubes equipped, clockwork motor, appearing in 1953.
Nagra II CI   The second generation fitted with printed circuit boards replacing chassis wiring, appearing in 1955.
Nagra III NP   The first Nagra usable for film work, first appearing in 1962.
Nagra IV-L   Monaural, featuring two microphone inputs and a built in audio limiter. Introduced in 1968.
Nagra 4.2   Same as the IV-L, but added powering for microphones and built-in equalizers. Introduced in 1972. In the '80s one could upgrade a Nagra 4.2 to record SMPTE timecode.
Nagra IV-S   Stereo Nagra, recording two track stereo. It had dual level pots, limiters, and equalizer presets. It was introduced in 1971. Originally it was available with a pilottone crystal, and then in 1984, with timecode support. With timecode support an IV-S became a Nagra IV-STC.
Nagra IV-SJ   Stereo Nagra for instrumentation and logging. Pots are replaced with switches to set gain in precise steps, no limiters, and when present, the microphone inputs are for high voltage unbalanced instrumentation mics rather than low impedance balanced with T-power and phantom.

In addition to these field recorders Kudelski S.A. produced also a studio recorder called the Nagra T-Audio, designed mainly for use in telecines for transferring dailies. All of the above machines use 1/4" tape.

Kudelski SA have also produced a famous series of miniaturised reel to reel recorders using 1/8" tape. These machines are referred to as SN (for Série Noire) and production was originally ordered by President Kennedy for the United States Secret Service. The SN range comprises the following models:

nagra snNagra SNN   monaural, full-track, main tape speed of 3-3/4 ips.
Nagra SNS   monaural, half-track, main tape speed of 15/16 ips (multiplying the recording length at the expense of the dynamic range and high-frequency response).
Nagra SNST   stereo, intended more for security service.
Nagra SNST-R   full hi-fi stereo. A special version of the SN using unique tape cassettes was made in cooperation with JBR Technology and widely used by US domestic intelligence agencies.

The Nagra IV-STC was the standard for film and classical music recording until the mid-1990s, when DAT recorders became reliable enough to use in the field. In response, Kudelski produced two digital recorders in order to compete:

Nagra D   4-channel PCM digital audio recorder. Instead of recording to the DAT format, the D used a digital reel to reel format using a helical-scan head and 1/4" tape on 5" and 7" reels. The unique format, combined with its heavy weight made it somewhat unpopular with many production sound mixers, but year after year many great-sounding films were completed with Nagra Ds and the newer 24-bit/96 kHz Nagra DII.
Nagra V   2-channel PCM digital audio recorder, 24-bit/96 kHz, removable hard drive based recorder with timecode support. This recorder has the additional benefits of being very light, and producing files easily processed by non-linear editing systems. Unlike the analog Nagras, the Nagra V digital recorders have not been adopted as readily for the motion picture and TV industries.
Nagra VI   In 2008, Nagra has introduced the Nagra VI, a portable 6-track digital recorder touted as "the natural successor to the NAGRA-D / DII multi-track digital recorders."

Wikipedia, the free encyclopaedia (Nagra)
Nagra Audio official website (Nagra 4.2 product outline)

Nagra 4.2

This one pictured is my only Nagra. It's a mint 4.2 with lime-green knobs.

nagra 4.2The Nagra 4.2 is a portable, mono full track 6.35-mm (¼ inch) analogue audio tape recorder designed for radio, cinema and television applications. This recorder has three speeds: 38, 19 and 9.5 cm/s (15, 7 ½, 3 ¾ ips), NAB or CCIR standard. Two mic. inputs, switchable to dynamic, T or P (48V) condenser. One voltage or current line input. One direct mixer input, 4.4V or 1.55V balanced line output, depending on the transformer installed. The NAGRA 4.2 contains separate recording and playback heads for confidence playback, built-in monitoring speaker switchable to source or tape, a reference generator, modulometer, alarm indicator for power supply and tape transport. It also has high-pass filters for recording or playback and a switchable automatic level control and limiter. Nagra's reel to reel tape recorders have an amazing reputation in the broadcast and film industries. While many modern productions now use their digital equipment, there is still a headstrong band of analog purists who insist that vintage Nagra gear is unbeatable. Whatever the truth, these machines are beautiful masterpieces of engineering.

The monaural Nagra 4.2 was launched first time in 1971. Listening to my first recording made with 19 cm/sec (7,5 ips) tape speed I was pleasantly surprised that its monaural sound doesn't mean monotony, quite the contrary, it clearly means absolute authenticity. Very soon the sonic quality of this recorder has resolved all my doubts about mono sound. I've noticed with satisfaction that monaural systems can be full-bandwidth and full-fidelity and are able to reinforce both voice and music effectively. Well, with live recordings of certain genres it can be even an advantage of mono that all listeners hear the very same signal and sound level.
A nice feature of the Nagra is the "practicality" of power. Besides of the external AC power from the ATN-2 mains power supply, which is connected on the recorder with a 6-pin Touchel connector, it can run also on classic "D" cell battery, a standard power unit found everywhere. Unlike many new technology devices that work only a few hours on their custom build batteries, the Nagra 4.2 can work like a race horse for days on one set of twelve "D" cell batteries.

The Nagra 4.2 analogue tape recorder was designed for radio, cinema and television applications and can be synchronized with motion picture cameras. Built for extreme ruggedness and reliability, Nagra Kudelski tape machines not only have set the standards of sound recording systems for motion picture productions, most of them have also outlasted decades in good condition in spite of professional use. No wonder that these marvels from Switzerland became highly desired collector's items. Alike StellaVox, Nagra tape recorders are true masterpieces of sophisticated mechanical and electrical engineering - Swiss made.

The Nagra 4.2 explained in english language, written by Fred Ginsburg nagra 4.2 in english .
The history of Nagra-Kudelski explained in german language nagra 4.2 in deutsch (this link gets you to the Analogue Audio Association website, (Unsere Zeitschrift) "Die legendären Nagra Geräte").

Maintenance of professional vintage audio equipment in Austria and Switzerland:

  Revox in Perfektion..., Michael Müller, successor of Mr DiBenedetto, Switzerland
  Austrian Analog Audio... Mr Anton Straka, Austria (abandoned website)