Sony CDP-XA55ES
(1998 - 2001)

Ultimate ES CD player of the last "classic" years, last evolution of the CDP-XA7ES with, give or take, the same mechanical build quality.

Three R-Core transformers (the same as in the CDP-MS1 / CDP-X5000 or SCD-1 / SCD-777ES) but not the two-in-one Twin Core molded into a big block of shielded resin as in the original XA7ES... The power-supply is also somewhat reduced and definitely gone was the luxury of copper-plating the chassis as in the "real" classic X7 players of the 1980s, 1990s and said XA7ES.

Where the XA-55ES really changes is in the added 24-bit VC24 filtering and S-TACT signal treatment : the former for tailoring the low-pass filter's frequency response, the latter to refine the way digital signals are deciphered, handled and transmitted. S-TACT is covered on TVK in one of the SCD-1's page pop-ups (direct link) and VC-24 also is (direct link).

Other niceties but not necessarily necessties when compared with the original XA7ES are "off-centered" insulators (for less vibration transmission through layout symmetry), Frame & Beam chassis (à la SCD-1 or... the much earlier ESPRIT TA-E900 and ESPRIT TA-E901 :) and a reinforced diecast zinc base around the optical pickup.
Gone however were, for instance, the cast-iron feet, the second anti-vibration top plate, the XLR and FET-charged outputs or SEPP headphones' plug : if the XA55ES shared the same KSS-273A laser as the original XA7ES, it "only" was an X5 and not an X7.

Pity Sony didn't carry a decade long evolution like those of the X7 series for the XA7 - or XA5. But then, in 1999... SACD was finally there !

All about the chips inside the CDP-XA55ES, right here.