If the display and audio sections were home-made, Denon's late entry into the home DAT format was made with an OEM base from Panasonic, ie. with the indestructible RAA1001 mechanism.
The d/a section is Denon's 20bit Lambda (LAdder from Multiple Bias DA) : dividing the PCM stream in two (positive / negative) to avoid zero-cross distortion ; this is done at the MSB level and the two d/a ICs themselves are BurrBrown's PCM61P.
The a/d section is (I believe) an 18bit delta-sigma, the digital filter is an NPC SM5813APT and SCMS is inside, of course.
The rest is nothing too distinguished : pressed metal chassis, "lightweight" 8,5kg weight and a basic plastic remote. T-Tag comes, previsibly, from Columbia and some batches even had a "Columbia 80th anniversary" badge added.
The DTR-2000G sold well but is nowadays sought after not for its sound, beauty or features but for its RAA1001. Denon's portable DAT recorders were also OEM'ed, from Casio.
The DTR-2000G also existed in black fashion (export mainly) under the DTR-2000 name. And it also existed in Japan as a Lo-D (Hitachi) DAT-8000.
See the Technics SV-DA10 for another view of the RAA1001 and this japanese page for nudies.