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Here we encounter various 300 sub assemblies. I spotted enough mother boards to build 160 amps. At about $20.000 retail each in Switzerland, that's significant production volume for a niche model. And yes, this was the first run which had to satisfy initial dealer and early customer orders. Matthieu Latour joked how he was "dead already. I've promised them delivery months ago. If you want to take any forbidden photos, go ahead. They can't kill me twice."

Here is the main 4-layer circuit board whose outward appearance doesn't betray the considerable complexity of three-dimensional 100 micron traces crisscrossing inside its modest thickness. The blue trim posts are of course for the 300B bias current. Adjustments are dialled in with the modulometer.

Here we see the same bias pots as actual users will—hidden beneath top-panel opening—and the corresponding display selector and modulometer readout.

Here we're back with the mother board from its other side...

... and a stack of another 40 amps in the making.

One half of the power supply surrounding the mains transformer...

... and the other half with a mains filter.


One side of the 300i input board...


... and the other side.


Here we're at a 300 test station for the signal circuitry. Its lid was a repurposed Nagra tape-recorder cover.

The test station power supply connected via flying leads and a massive multi-pin socket.

The JJ power tubes—Nagra necessarily has to provide current rather than NOS valves and acquired an initial inventory of 700 bottles from this Slovak supplier—hung upside down for the occasion.

Here is the equivalent test station for the 300's power supply circuitry without an operator...

... and with.

A closer look at how the supply terminated into load resistors for the occasion.

Here is a 300 input board being put through its paces.


Elsewhere in this area a lady judge checked up on a fully assembled MSA.

Nagra prides itself on being an equal-opportunity employer. Their machine shop for example is run by a young lady. The assembly area here had more women than men.

Test gear at Nagra mushrooms as though it was cheap Electric Avenue kit rather than serious Audio Precision laboratory stuff.