Any acoustical engineer can tell you about the four phases of a sound when struck by a key: 1) attack, 2) decay, 3) sustain, and 4) release. ADSR describes the “envelope” of a single sound from beginning to end. Every instrument has its own distinct ADSR profile. The ADSR of a pipe organ is significantly different than the ADSR of a celeste, for example. But the real goal, every engineer’s holy grail, in addition to the creation of realistic string sounds, clarinets, trumpets, church organs, timpanis, etc., is to recreate 100% the ADSR for every note on a Steinway Concert Grand (Model D), arguably the most acoustically complex instrument ever invented. The first “breakthrough” came in the 1980′s by MIT Scientist, Futurist, and Entrepreneur, Ray Kurzweil, who “sampled” a Steinway. That is, instead of synthesizing, he carefully recorded and digitized each note. His Kurzweil Digital Piano was unveiled with all sorts of hoopla at the 1986 NAMM (National Association of Music Merchants) Convention, Anaheim, CA. Even Robert Moog, the inventor of the legendary Moog Synthesizer, who had worked on the project, called it the greatest advance in acoustical engineering since, well, the invention of the Steinway. Yet despite the best efforts of Messers Kurzweil, Moog, and others over the years, there remain too many unaccounted-for factors in the ongoing pursuit of that perfect Steinway sound. To name just a few: wood variables, resonances, string chemistry, and electronic variables like miking, amplification, speaker baffling, and a hundred other issues which, when added together, cannot really come close to the rich — and genuine — sound of a Steinway. But, hey, anything’s possible. Keep trying guys!