Digging into the specifications for the Pa3x, one can't help but wonder where the sound engine came from. The specifications state:

PA3X
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"Enhanced RX (Real eXperience) sound engine offers improved realism and new vivid sound, including pianos borrowed from the acclaimed Korg SV-1 Stage Vintage Piano, plus Ambience Drums"

KORG EDS (Enhanced Definition Synthesis) sound generator: 120 Voices, 120 Oscillators – RX (Real eXperience) Technology - DNC (Defined Nuance Control) - Natural Ambience Drums Sound - Filters with Resonance - Three band EQ for each track

PA2X
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KORG EDS (Enhanced Definition Synthesis) sound generator: 120 Voices, 120 Oscillators – Filters with Resonance - Three band EQ for each track


They didn't borrow any technology from the Kronos or the Oasis other than the EDS sound engine. It looks like it's the same sound engine from the Pa2x. They may have upgraded the effects and filters a bit since they added "ambience" drums.

So sound wise, I don't see where there is any difference from the Pa2x; ON PAPER.

Same Sound engine, same RX Experience = Same Sound.