A truly "no expense spared" recording machine distributed mainly in Japan and very little elsewhere.
It wasn't, however, a groundbreaking unit but rather one which embodied all the savoir-faire Sony accumulated with its cassette decks since the 60s and, more specifically, since the last ES team was officially put together in 1986.
From the acclaimed and very successful TC-K777ES (1982) to the TC-K700ES (1986) to the ultimate TC-K990ES classic (TC-K555ESJ in Japan, 1992), the TC-KA7ES took all that was good and refined the formula even further : all the way down to 6N pure copper wiring.
From the staple LA Heads (Laser Amorphous), to the Lapis-Lazuli bearings, the copper-plated everything, gold-plated terminals, gold-plated heads, Sony's own Dolby S ICs, the ceramic casstte holder, the huge R-Core twin transformer, GIC filter, the fully dual-mono audio board, FET i/os and more, plus, at the center of all this, the famed TCM-200D drive assembly here in its ultimate iteration : TCM-200D17.
However, surprisingly, in spite of all this, the KA7ES didn't cost that much in Japan : 120,000¥. Accounting for this is the fact that, in 1993, all tape-based formats were on their way out no matter the quality or features...
Available in black or champagne, the latter selling much better. The export model was the slightly less-featured TC-KA6ES but it seems some KA7ES made it outside Japan.
The TC-KA7ES was and still is the ultimate cassette recorder -bar none- and with it Sony's glorious history of analog recording did really end.