The Nagra IV-S Portable Audio Tape Recorder
What can one say about what is probably the most successful and long lived portable
professional tape recorder ever made? Certainly the 'Nagra' was a legend in it's own lifetime,
and remains an object lesson in quality of engineering together with remarkably simple and
unpretentious functionality. Beautifully made and until a few years ago just about every film and
television programme produced had its sound recorded on one of these impeccable machines.

Nagra portable film sound recorders similar to the above machine became the de facto film
industry standard for more than a quarter of a century, and were only gradually edged out of use
in the last decade by firstly; compact R-DAT recorders, and now by various short-lived and
almost disposable file based devices. As with professional video, the new technology seems to
be doing anything but establishing any industry certainly or commonality of format.

The Nagra IV-S shown above is an immaculate late time code machine type NQS-TCC, which
might indeed be still available new from the factory, and I wish it was part of my own
collection...

The June 1989 Audio and Video Product Line catalogue describes it thus:

'The NAGRA IV-S is a portable self contained 6.35mm (1/4") tape stereo recorder designed for
high quality musical recording, cinema and television applications. It has three speeds: 38, 19
and 9.5 cm/s (15, 7 1/2 and 3 3/4 ips) NAB or CCIR, plus NAGRAMASTER (38 cm/s only /
15ips) equalizations. The machine has two microphone inputs with three pin XLR connectors,
switchable between dynamic, "T" or Phantom powering, with phase check, and left channel
phase reverse switch, or two current line inputs. It also features a NAGRALIN antidistortion
system, high pass filters for recording or replay, and a switchable automatic level control and
limiter. Built-in loudspeaker, and headphone output and reference signal generator. The machine
can be fitted with a NAGRASYNC F.M. 50/60Hz pilot system or the SMPTE/EBU centre-track
time code system, including a built-in time code generator, for synchronizing. Other accessories
are available for particular applications.'
Above is the tape head area, moving from left to right we have; the dual-gap ferrite erase head,
the time code record/replay head, the audio record head and finally the audio playback head. In
this photograph the tape path has been opened for lacing and the hinged audio head screening
shields are folded down. One might like to appreciate the substantial tape guides and the massive
stroboscopicaly marked flutter idler wheel. Every component looks simple, honest and beautifully
engineered. This version of the machine uses a later type of tape guide which have a slightly
textured though very hard white ceramic face plate, together with (unique?) ruby rod end stones.
Apparently the ceramic face plates replaced solid polished slices of synthetic ruby used in the
previous version of these guides because it tended to cause a slight stiction or judder effect with
the tape which could increase scrape flutter. Visible just in front of the central time code
record/replay head is the unique Nagra azimuth adjusting device. This consists of a pair of very
slightly wedged disks sandwiched under each record and play head, one was fixed to the deck
plate and the other had a geared circumference. To adjust the head azimuth one just turned a small
socket headed gear wheel at the front of the head with an Allen key, and this rotates the two
wedges against each other, thus rocking the head back and forth. As far as I am aware this system
was fitted to all Nagra portables, though can't recall if it was used on the T-Audio.
Left side of the Nagra IV-S, containing the various noise-reduction and line inputs and outputs,
together with the XLR microphone inputs and their powering mode and attenuator switches. One
of the many nice touches are the slotted carry-strap 'keepers' (extreme left).
Right side of the Nagra IV-S showing the loudspeaker grille together with the various power
and time code connections.
And if you ever wanted to know what the underside of a Nagra IV-S looked like... (The
rectangular door is the simply fastened battery cover, which can, if you don't keep hold of it,
just fall on to the floor.)

(Click on any of the above pictures to get some images of the interior of the machine.)