Many happy rewinds: the Nagra III at fifty

In the early 1950s Stefan Kudelski, an engineering student in Lausanne, built himself a portable tape recorder. He came up with something of such quality that it was to leave a significant mark on audio engineering practice; he called it the Nagra. Following models I and II, which according to official company history sold themselves by word of mouth, the Nagra III was the first model to be fully electronic.

The III was also the first model to be mass-produced; more than 10,000 were made. From the first this was a machine intended to allow professionals to record sound at minimum notice, in the widest variety of environments; European broadcasters had been buying Nagras from the model I and their needs were well-defined. The machine contained everything required and nothing else; but as much as cramming a piece of recording equipment – and its power supply – into a box barely big enough to hold a packed lunch was a triumph in 1951 when the first Nagra appeared, fitting the mechanism and electronics of a tape recorder with a technical specification at least as high as a full-size, 30 or 40kg studio machine into a case not much larger than that was almost miraculous.

Perhaps more remarkably still, the result was more than just visually satisfactory. It was stylish, and it still looks good. The case, made from aluminium to save weight and provide resilience, is well proportioned and not overloaded with controls; the whole machine is finished either in bare metal or grey metallic hammerite, with labels on a gloss black panel. The layout of the deck is straightforward and clear. Detailing is confident and never fussy, and there are no extraneous flaps or lids concealing anything. There is only one anomaly: the XLR socket for a single microphone (no stereophonic recording here, thank you!) projects from the left hand side. But its use is justified: it provides a right-angled connection so that the plug on the mike lead is aligned with the case rather than jutting out awkwardly.

One striking visual aspect of the III is a repeated circle motif. Circular forms appear everywhere; on the front panel, controls are protected from accidental movement by circular cowls, the multi-purpose 'modulometer' is in a circular case and there are (incidentally) two circular 4mm sockets to round things off. On the deck, which forms the whole of the top of the case, not only are the various rollers of necessity circular in plan, but the tape transport control, rotated to engage the tape drive, and the pinch wheel are both on circular base plates. Large flat-headed screws fasten the deck to the case, and the fact that each screw sits in a square box highlight in the etched deck plate emphasises their circularity. The corners of the case are rounded. Lastly, the plastic lid with its rounded catch has circular raised sections over each reel.

The deck is a composition in its own right; though the heads, rollers and controls are placed where mechanics require them to be, they happen to group into satisfying clusters; the symmetry of the supply and take-up reel tables and the tension rollers is set off by the asymmetry of the tape guides, flutter rollers, capstan and heads. The whole surface of the deck is etched to give a satin finish; the manufacturer's name appears in polished metal relief along with a set of outlines that mark 'clear zones' around the reels and the tension rollers; a helpful direction arrow is also given, just in case the novel appearance of the machine should prove so offputting as to make a user think that, contrary to every other tape machine produced, the tape plays from right to left.

The controls on the front are superbly well-labelled in bold sans-serif capital letters; the size of each control is such that text approaching 12pt in size fits happily. The text is reversed out of a gloss black panel printed on polished bare metal; it is high-contrast, correctly set, and highly legible. In one of the few concessions to styling, a horizontal band formed of two lines runs across the whole panel, right through the centres of the three rotary controls.

The machine’s well-composed look has been achieved through good engineering, sensible ergonomics and taste. It is a miraculously harmonious piece of work; the striking resemblance between it and the very sleek Apple MacBook Pro and G4 PowerBook of recent past may not be coincidental.

Visual characteristics, of course, were not of great interest to technical reviewers of the machine when it was a production workhorse. Instead, its good-quality sound, ruggedness and practicality were the important facts. Despite sensible cautions in the user manual, Nagras were built to survive very rough treatment; they would not have earned their place in the location sound environment if they had not been tough. They also had to consume as little power as possible; the first machines Kudelski built ran on clockwork and had valve electronics, but the III uses a selection of germanium transistors and is powered by 12 D cells. These contribute significantly to the machine's weight in operating condition and provide another good reason for the use of aluminium throughout the machine.

Internally, it is a miracle of simplicity; naturally the mechanical engineering is as accomplished as the controls and layout above deck imply. The transport is driven by a single large motor. One end of its spindle emerges through the deck to form the capstan, and a 'phonic wheel' is attached to the other. The wheel forms the sensing part of a feedback circuit that holds the motor's rotation speed constant in record and playback modes. It is the high quality of the motor and the use of controlling electronics that gives the machine its good sound quality, and in contrast to large contemporary console or tabletop tape recorders, the motor is small, lightweight and precisely engineered.

Kudelski’s company deserved success from the III, and they got it. The machine was very expensive, but it gave dependability when that was most appreciated: location sound recordings can rarely be attempted repeatedly, and the locations are often far from ideal for operating machinery. When it was introduced, there were no competitors; by the time it was replaced by the model IV there were. The ever-advancing miniaturisation of electronic components, and the success of the III, saw to that. The III is an acknowledged icon of audio recording; it is also a design icon, its controls and layout combining aesthetic satisfaction with fitness for purpose in a manner so straightforward it seems inevitable. There were to be a further thirty years of analogue audio recorder design progress, but this machine, in its own right, was fully evolved.