I do recall the PA 60/50 NOT having any sounds that will be velocity switching by the factory or better said, the technology in those arranger generation did not have it....you may program them using on board sounds, but, the sounds you are talking are the RX, and those where introduced with the PA1X/PA1XPro at the time, and now is available with all the new PA 2X, 800 and 500/588.
By the way, now they have in the PA2X and 800 with the new OS 2.1 added the new tone generation the "DNC Defined Nuance Control", basically similar to the SA2.


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mdorantes