In the -80ties the typical sound of a real acoustic piano and electric pianos was produced by the “Real thing” or the “Roland MKS-20”, those where the days long before multisampled multivelocity sound libraries like our Dusty Electric MK II or the "Pianoteq" physical modelling software.
Starting in the mid -80ties and continuing to this days the MKS-20 has been "signature" and an important part of forming the sound of modern music production in many genres like rock , pop and (do not forget...) the classic House/dance piano sound (Piano preset 3).
The MKS-20 by today’s standards is not "authentic", like the TR-808 and TR-909 wasn’t "authentic", still its own character is essential and a "must have" for all music producers!
The Roland MKS-20 was based on a technique called "structured adaptive synthesis", an early form of physical modelling.