Penultimate full-fledged pre-Esprit to appear, late in 1978 in Europe and Japan, a year later in the USA.
The FM-only J88 was produced at the time Sony and Wega in Germany were pondering about the presence or absence of an ESPRIT tuner. The latter was finally made but only by Wega and not carried into the Sony ESPRIT lineup.
Digital displays were cool and "efficient" but one still had to slide in from above the set of little pre-cut cards to name the digits :-)
Sound-wise, contrarily to the other 86 and 88 units which call for unanimous praise, it seems the ST-J88B is not a "super tuner"...
Having spent some time with both the ST-A7B and the ST-J88B (and still owning both), it is obvious the J88B cannot touch just about anything the ST-A7B has.
Maybe an ageing problem (caps, alignment etc) or simply the fact that the effort mainly went into the digital circuits and automation and not in the audio section per se.
The japanese J88 has completely different boards and a toroidal transformer so maybe some of the "finesse" was lost in this strange change of componentry... See one here.
The J88B nevertheless is a very good, "musical", source and, of course, the ST-A7B puts the quality level very high !
But the addition of it and the TC-K88B were of late conviction and mainly to supplement the N86B / E86B and E88B bestsellers.
The silver (J88) was for Japan only ; the rest of us got the gunmetal grey : J88B.
The J88B is the most elegant unit of the series and one of the most elegant of all (digital) times, with the Kyocera T-910.