A fairly rare beast sparingly distributed, even in Japan. It was ranked "below" Denon's own Japan-only digital TU-1000 tuner which seems to have sold... not at all :)
As the previous Denon tuners, the meters can be used for signal/multipath indication, broadcast level or to monitor the level of an external source, through a set of speaker posts. A 400Hz cal generator is at hand, alongwith a moderate 1-position high-blend, wide/narrow IF and muting switches, plus fixed and variable outputs.
Sorry, no presets !
Slightly heavy design (I grant you it is austere indeed) which nevertheless vanishes completely when a good quality station happens to be at hand !
Not only is this 5-gang, FM-only, Mos-Fet-charged tuner quite refined but, paired with an outdoor antenna, it could make one wonder if spending so much on one of the well known super-tuners is a necessity :-)
If bass isn't the most present element (I for one would say it is evenly balanced), the medium region is magnificent, allowing a real sense of depth and height. Highs and sibilances remain quite detailed and well contained, respectively.
At 79,000¥ when introduced, this wasn't meant to be an absolute market topper - if only today's mid-end units were as good as this... we perhaps wouldn't regret the late 70s period.
I cherished for five years my own TU-850 - it is absolutely non-fatiguing, dead silent, and makes one want to listen more and more and more and more. After all, FM is a free source and there's no getting up to flip sides :-)
But definitely upper class (world-class topper that is) was and still is the Sony ST-A7B.
Thanks to Grzegorz, more inside images can be found here ; a review is of course available at the fmtunerinfo website.