Particularly regarding the Instrumentation Nagra SJ, an audiophile client was asking me what made the Nagra sound “special.” The SJ has “extended frequency response” to allow for measurment of vibrations and supersonic artifacts. Does it sound better? Is it the amplifier design?
The SJ is not necessarily going to sound better. The SJ recording system did not include the same pre-distortion tricks that are employed in the audio Nagras. As you go up in record level, saturation and non-linearity increase. Pre-distortion served maintain that linearity. Otherwise, the SJ has NAB/CCIR record and playback EQ like any other Nagra. The head gaps on the SJ’s were narrower, to allow for higher frequency recording and playback at 15ips. The specifications have the response at 35khz at 15ips. ….Nagras were often built to order, with unique circuitry combinations based on what the individual customer needed. Along with circuit improvements/changes done at the factory, (many undocumented) there’s hundreds of different Nagra configurations. There were even Nagras built without a front meter or input level controls, just a blank panel (Nagra IV-ML) These days, every Nagra I encounter is different in some way from the norm.
The Nagra playback amplifiers are simple, discrete transistor designs. I’ve had clients who own outboard tape head pre-amps they’ve paid $4000 for, like the “King Cello” preamp, so they want the outputs of the heads available on the side panel of the Nagra. For example see http://www.reeltapes.net/kingcello -one of these expensive preamps.
Using the Nagra in a home music playback environment goes beyond the sound of the internal amplifiers. Users also appreciate having a very unique, professional, portable recorder. Stereo Nagras sold back in the 80’s for around $10,000. The build quality is remarkable, with no stamped parts, only machined aluminum/stainless steel parts. The functionality and durability were designed to withstand constant use in extreme environments and temperatures. The servo motor speed control can maintain perfect speed while the recorder is dropped to a table, or while the user is running on foot with the recorder on the shoulder. The tape tension mechanics are ingenious, continually self-adjusting tape tension during transport operations. The aesthetic design is a direct reflection of Kudelski’s sensibilities, from the unusual dual-needle meter, to the use of excessive panel labeling. Kudelski’s electronic designs were not complex, but all component values, tolerances and other characteristics were carefully regulated. All transformers and inductors (using toriod cores only) are wound entirely in-house. All fasteners are made of stainless steel. It is a laboratory-grade instrument that found its primary home in the alternative universe of motion picture production. That the film art-form once required such elegant, yet precision equipment is part of the Nagra’s allure. -by Pete Verrando www.txsound.com