Sony ESPRIT TA-N902
(late 1983 - 1986)

Here is other x-rare Sony ESPRIT unit : the one that appeared last, when the entire ESPRIT adventure was about to be shelved, forgotten and abandoned. Too bad - it is the best of the series.

The TA-N902 bears no technological similarity with the TA-N901, nor the original TA-N900 : no Heat-Pipe, no PLPS, no slimline design , and no ultra-high frequency response as in the TA-N9. Just two very beefy transformers, four ELNA For Audio 22,000µf caps and large visible heatsinks - powerhouse old style.
The power transistors are Hi-fT bipolars as in the TA-N86B bestseller and not MOS-Fet as in the N900 but the N902 did keep the pure Class A output as in the TA-N900 monoblocks. The two power transformers were also used in the contemporary but Japan-only TA-F777ES (not to be mistaken with the ultimate TA-FA777ES !).

The reason why Sony waited so long to launch this ultimate ESPRIT component, more than three years after the N900s and two after the N901s is multi-fold and I won't go into that here. But it partly had to do that the Sony engineers wanted to use a special oxygen-free cable for the wiring which Hitachi was working on when the N902 was put under development in 1981.
So... Sony waited on Hitachi. A strange move however : Sony was among the first, if not the first, to develop its own highend loudspeaker and modulation cables (RK series) since the early 1970s, even offering Litz wires versions.
You can read a short version of this here on TVK - ain't this a complete website ?

The "Visual Communication Display" here sports a green indicator that turns red when the heatsinks' temp exceeds 90°C and a peak meter with 6 level bars ; at power-on, the indicator is blue until the stages are warm enough to go green. Monoblock mode is possible, for a whopping 400W between 20Hz and 20kHz - in Class A.

Anyway - the TA-N902 arrived on the scene too late, complementing earlier siblings which, however good and respected, were all old as the hills in 1984 : TA-E900, SE-P900, TA-D900. It was welcomed briefly, sold rather well in Japan, barely in Europe. That's it. Too bad : it is the best of the series.

Click the buttons below for schematics, circuit descriptions and specifications - ain't this a complete website ?