Ivory uses samples. Each key of the piano is painstakingly recorded hundreds of times at different dynamic levels and with different pedaling. When you “play” Ivory, you replay the samples.
Pianoteq is modeled from first principles. It is based on the mathematics of keys, dampers, hammers, strings, and soundboards. When you “play” Pianoteq, you solve a differential equation that describes the physics of an ideal piano.
Neither approach is perfect; both lie somewhere on the upslope of the uncanny valley. Ivory’s samples can’t capture the full quality of pedaling and sympathetic resonance. And I often catch Ivory repeating samples at unexpected times; nobody wants deja vu when tickling the ivories.
Pianoteq can’t yet capture the dirt and nuance of real hammers on real strings. But the latest version has made such great strides that it has won me over. The underlying hammer/string model is, to my ears, substantially improved. Pianoteq feels alive under my hands and plays closer to the real thing than anything else I’ve tried.
Beyond this, I simply love the idea that we can master the physics that govern the piano and channel them into an artistic and technical achievement of first rank. Here’s the principal equation for audio evolution, as described in Pianoteq’s original patent application:
I almost don’t care that this is a standard exciter/resonator model, or that it’s left as an exercise to the reader to produce the tables behind the key coefficients, or that I haven’t studied equations of this sort in over a decade and am out of my mathematical depth.
I’ll just let its form wash over me. It’s kind of beautiful, no?