The piano is a versatile and mature instrument. One reason for its popularity is its wide timbral range; in fact, its main innovation was the ability to play notes both loud and soft, hence "Pianoforte" (its full original name).
To make AMY into a truly general-purpose music synthesizer, we wanted to add a good piano voice. But it's not simple to synthesize a good piano voice. This page explains some of what makes piano synthesis challenging, and how we addressed it. Our approach was to use additive synthesis, which nicely fills out the demonstration of the primary synthesis techniques implemented in AMY, after subtractive (the Juno-6 patches) and FM (the DX7 patches).
This clip starts with a D4 note played at three loudnesses - pp, mf, and ff. These are followed by a D2 (two octaves lower), and a D6 (two octaves higher). (I made this example by adding together isolated recordings of single piano notes from the University of Iowa Electronic Music Studios Instrument Samples, which are the basis of the AMY piano. I combined them with the code in make_piano_examples.ipynb.)
Electronic musical instruments have always taken inspiration from their acoustic forbears, and most electronic keyboards will attempt to simulate a piano.